Update codenotify.yml

Author: nicksnyder

.github/workflows/codenotify.yml

@@ -10,7 +10,7 @@ jobs:
       - uses: actions/checkout@v2
         with:
           ref: ${{ github.event.pull_request.head.sha }}
-      - uses: ./ # If you were using this in your project, this would be sourcegraph/codenotify@v0.4
+      - uses: ./ # If you were using this in your project, this would be sourcegraph/codenotify@vX.Y.Z (check releases on GitHub for latest version number)
         env:
           # This token needs to have repo scope and read:org scope (to be able to mention teams).
           GITHUB_TOKEN: ${{ secrets.CODENOTIFY_GITHUB_TOKEN }}