chore: bump elixir-protobuf to 0.15

deprecated functions have been removed, so they've been replaced with
a struct definition

regenerate pb.ex files

```
❯ protoc --elixir_out=. --elixir_opt=package_prefix=astarte.core lib/astarte_core/proto/*.proto
❯ protoc --elixir_out=. --elixir_opt=package_prefix=astarte.core.triggers lib/astarte_core/triggers/*.proto
❯ protoc --elixir_out=. --elixir_opt=package_prefix=astarte.core.triggers.policy_protobuf lib/astarte_core/triggers/policy_protobuf/*.proto
❯ protoc --elixir_out=. --elixir_opt=package_prefix=astarte.core.triggers.simple_events lib/astarte_core/triggers/simple_events/*.proto
❯ protoc --elixir_out=. --elixir_opt=package_prefix=astarte.core.triggers.simple_triggers_protobuf lib/astarte_core/triggers/simple_triggers_protobuf/*.proto
```

Signed-off-by: Francesco Noacco <francesco.noacco@secomind.com>

Author: noaccOS

lib/astarte_core/proto/astarte_reference.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.AstarteReference do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "AstarteReference"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :object_type, 1, type: :int32, json_name: "objectType"
   field :object_uuid, 2, proto3_optional: true, type: :bytes, json_name: "objectUuid"

lib/astarte_core/triggers/policy/handler.ex

@@ -115,10 +115,10 @@ defmodule Astarte.Core.Triggers.Policy.Handler do
       strategy: strategy
     } = handler
 
-    HandlerProto.new(
+    %HandlerProto{
       strategy: Map.get(@strategy_string_to_atom, strategy),
       on: error_type_to_tagged_error_tuple(error_type)
-    )
+    }
   end
 
   def from_handler_proto(%HandlerProto{} = handler_proto) do
@@ -134,12 +134,13 @@ defmodule Astarte.Core.Triggers.Policy.Handler do
   end
 
   defp error_type_to_tagged_error_tuple(%Policy.ErrorKeyword{keyword: keyword}) do
-    {:error_keyword,
-     ErrorKeywordProto.new(keyword: Map.get(@error_keyword_string_to_atom, keyword))}
+    error_keyword = %ErrorKeywordProto{keyword: Map.get(@error_keyword_string_to_atom, keyword)}
+    {:error_keyword, error_keyword}
   end
 
   defp error_type_to_tagged_error_tuple(%Policy.ErrorRange{error_codes: codes}) do
-    {:error_range, ErrorRangeProto.new(error_codes: codes)}
+    error_range = %ErrorRangeProto{error_codes: codes}
+    {:error_range, error_range}
   end
 
   defp tagged_error_tuple_to_error_type({_, %ErrorKeywordProto{keyword: keyword}}) do

lib/astarte_core/triggers/policy_protobuf/error_keyword.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.PolicyProtobuf.ErrorKeyword.KeywordType do
   @moduledoc false
 
-  use Protobuf, enum: true, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "ErrorKeyword.KeywordType"
+  use Protobuf, enum: true, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :INVALID, 0
   field :ANY_ERROR, 1
@@ -14,9 +12,7 @@ end
 defmodule Astarte.Core.Triggers.PolicyProtobuf.ErrorKeyword do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "ErrorKeyword"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :keyword, 1,
     type: Astarte.Core.Triggers.PolicyProtobuf.ErrorKeyword.KeywordType,

lib/astarte_core/triggers/policy_protobuf/error_range.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.PolicyProtobuf.ErrorRange do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "ErrorRange"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :error_codes, 1, repeated: true, type: :int32, json_name: "errorCodes"
 end

lib/astarte_core/triggers/policy_protobuf/handler.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.PolicyProtobuf.Handler.StrategyType do
   @moduledoc false
 
-  use Protobuf, enum: true, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "Handler.StrategyType"
+  use Protobuf, enum: true, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :INVALID, 0
   field :DISCARD, 1
@@ -13,9 +11,7 @@ end
 defmodule Astarte.Core.Triggers.PolicyProtobuf.Handler do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "Handler"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   oneof :on, 0
 

lib/astarte_core/triggers/policy_protobuf/policy.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.PolicyProtobuf.Policy do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "Policy"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :name, 1, proto3_optional: true, type: :string
   field :maximum_capacity, 2, type: :int32, json_name: "maximumCapacity"

lib/astarte_core/triggers/simple_events/device_connected_event.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.SimpleEvents.DeviceConnectedEvent do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "DeviceConnectedEvent"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :device_ip_address, 1, proto3_optional: true, type: :string, json_name: "deviceIpAddress"
 end

lib/astarte_core/triggers/simple_events/device_disconnected_event.pb.ex

@@ -1,7 +1,5 @@
 defmodule Astarte.Core.Triggers.SimpleEvents.DeviceDisconnectedEvent do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "DeviceDisconnectedEvent"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 end

lib/astarte_core/triggers/simple_events/device_error_event.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.SimpleEvents.DeviceErrorEvent.MetadataEntry do
   @moduledoc false
 
-  use Protobuf, map: true, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "DeviceErrorEvent.MetadataEntry"
+  use Protobuf, map: true, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :key, 1, type: :string
   field :value, 2, type: :string
@@ -12,9 +10,7 @@ end
 defmodule Astarte.Core.Triggers.SimpleEvents.DeviceErrorEvent do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "DeviceErrorEvent"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :error_name, 1, proto3_optional: true, type: :string, json_name: "errorName"
 

lib/astarte_core/triggers/simple_events/incoming_data_event.pb.ex

@@ -1,9 +1,7 @@
 defmodule Astarte.Core.Triggers.SimpleEvents.IncomingDataEvent do
   @moduledoc false
 
-  use Protobuf, protoc_gen_elixir_version: "0.11.0", syntax: :proto3
-
-  def fully_qualified_name, do: "IncomingDataEvent"
+  use Protobuf, protoc_gen_elixir_version: "0.15.0", syntax: :proto3
 
   field :interface, 1, proto3_optional: true, type: :string
   field :path, 2, proto3_optional: true, type: :string