[chore] add explicit telemetry configuration to config.yaml files (#1405)

* [chore] add explicit telemetry configuration to config.yaml files

* address code review

Author: atoulme

distributions/otelcol-contrib/config.yaml

@@ -47,6 +47,19 @@ exporters:
     verbosity: detailed
 
 service:
+  telemetry:
+    metrics:
+      readers:
+        - pull:
+            exporter:
+              prometheus:
+                host: '127.0.0.1'
+                port: 8888
+                without_scope_info: true
+                without_type_suffix: true
+                without_units: true
+                with_resource_constant_labels:
+                  included: [ ]
 
   pipelines:
 

distributions/otelcol/config.yaml

@@ -47,6 +47,19 @@ exporters:
     verbosity: detailed
 
 service:
+  telemetry:
+    metrics:
+      readers:
+        - pull:
+            exporter:
+              prometheus:
+                host: '127.0.0.1'
+                port: 8888
+                without_scope_info: true
+                without_type_suffix: true
+                without_units: true
+                with_resource_constant_labels:
+                  included: [ ]
 
   pipelines: