[go] More idiomatic godoc comments (#10044)

* [go] More idiomatic godoc comments

* [go] Mark deprecated fields and functions

* [go] Minor mustache readability/consistency fixes

* [go] Mark deprecated operation parameters

* [go] Deprecate a petstore component property for testing

* [go] Apply deprecated godoc in Go servers also

samples/server/petstore/python-fastapi/openapi.yaml

@@ -76,7 +76,8 @@ paths:
       description: Multiple status values can be provided with comma separated strings
       operationId: findPetsByStatus
       parameters:
-      - description: Status values that need to be considered for filter
+      - deprecated: true
+        description: Status values that need to be considered for filter
         explode: false
         in: query
         name: status
@@ -773,6 +774,7 @@ components:
             name: tag
             wrapped: true
         status:
+          deprecated: true
           description: pet status in the store
           enum:
           - available