Whitelist contributors.yml in contributors.yml

Author: alandefreitas

.github/workflows/contributors.yml

@@ -6,6 +6,7 @@ on:
       - '**.md'
       - '.github/**'
       - '!.github/workflows/build.yml'
+      - '!.github/workflows/contributors.yml'
       - 'documentation/**'
       - '.clang-format'
       - '.gitignore'