chore: fix releases for gapic-common (#1014)

Author: dazuma

.release-please-manifest.json

@@ -1,4 +1,4 @@
 {
   "gapic": "0.1.0",
-  "gapic-common": "0.21.0"
+  "gapic-common": "0.20.0"
 }

gapic-common/.toys.rb

@@ -28,6 +28,11 @@
   t.fail_on_undocumented_objects = false # TODO: Fix so this can be enabled
   t.bundler = true
 end
+alias_tool :yard, :yardoc
+
+expand :gem_build
+
+expand :gem_build, name: "install", install_gem: true
 
 tool "ci" do
   include :exec, e: true

gapic-common/CHANGELOG.md

@@ -1,12 +1,5 @@
 # Release History
 
-### 0.21.0 (2023-12-12)
-
-#### Features
-
-* Drop support for Ruby 2.6 ([#1009](https://github.com/googleapis/gapic-generator-ruby/issues/1009)) 
-* Honor universe domain in stubs ([#1008](https://github.com/googleapis/gapic-generator-ruby/issues/1008)) 
-
 ### 0.20.0 (2023-08-31)
 
 #### Features

gapic-common/lib/gapic/common/version.rb

@@ -14,6 +14,6 @@
 
 module Gapic
   module Common
-    VERSION = "0.21.0".freeze
+    VERSION = "0.20.0".freeze
   end
 end

gapic/.toys.rb

@@ -28,6 +28,11 @@
   t.fail_on_undocumented_objects = true
   t.bundler = true
 end
+alias_tool :yard, :yardoc
+
+expand :gem_build
+
+expand :gem_build, name: "install", install_gem: true
 
 tool "ci" do
   include :exec, e: true