chore: comment out unused push triggers in test-site-builds-legacy workflow

- Disabled `push` triggers by commenting out defined path filters.
- Maintained `pull_request` and `workflow_dispatch` triggers for manual execution.
- Added note referencing the newer workflow: `nx-optimized-ci.yml`.

Author: jonphipps

.github/workflows/test-site-builds-legacy.yml

@@ -4,15 +4,15 @@ on:
   # Disabled - legacy workflow superseded by nx-optimized-ci.yml
   # push:
   #   branches: [main, dev]
-    paths:
-      - 'packages/**'
-      - 'standards/**'
-      - 'portal/**'
-      - 'scripts/**'
-      - '.github/workflows/**'
-      - 'package.json'
-      - 'pnpm-lock.yaml'
-      - 'tsconfig.json'
+  #   paths:
+  #     - 'packages/**'
+  #     - 'standards/**'
+  #     - 'portal/**'
+  #     - 'scripts/**'
+  #     - '.github/workflows/**'
+  #     - 'package.json'
+  #     - 'pnpm-lock.yaml'
+  #     - 'tsconfig.json'
   pull_request:
     branches: [main, dev]
   workflow_dispatch: