Disallow usage of pkg/errors and otlp proto module (open-telemetry#5785)

Signed-off-by: Bogdan <bogdandrutu@gmail.com>

Author: bogdandrutu

.golangci.yml

@@ -105,6 +105,16 @@ linters-settings:
     packages-with-error-message:
       # See https://github.com/open-telemetry/opentelemetry-collector/issues/5200 for rationale
       - sync/atomic: "Use go.uber.org/atomic instead of sync/atomic"
+      - github.com/pkg/errors: "Use 'errors' or 'fmt' instead of github.com/pkg/errors"
+    # Add a different guard rule so that we can ignore tests.
+    additional-guards:
+      - list-type: denylist
+        include-go-root: true
+        packages-with-error-message:
+          - go.opentelemetry.io/proto: "Use go.opentelemetry.io/collector/pdata instead"
+        # Allow in tests for testing pdata or other receivers/exporters that expect OTLP.
+        ignore-file-rules:
+          - "**/*_test.go"
 
 linters:
   enable: