Add missing path to workflow

Author: rrousselGit

.github/workflows/dart_frog_lint.yaml

@@ -4,6 +4,7 @@ on:
   pull_request:
     paths:
       - ".github/workflows/dart_frog.yaml"
+      - "packages/dart_frog_lint/example/**"
       - "packages/dart_frog_lint/lib/**"
       - "packages/dart_frog_lint/test/**"
       - "packages/dart_frog_lint/pubspec.yaml"
@@ -12,6 +13,7 @@ on:
       - main
     paths:
       - ".github/workflows/dart_frog_lint.yaml"
+      - "packages/dart_frog_lint/example/**"
       - "packages/dart_frog_lint/lib/**"
       - "packages/dart_frog_lint/test/**"
       - "packages/dart_frog_lint/pubspec.yaml"