chore(action): Clean up the README examples a bit

Author: avidal

README.md

@@ -12,6 +12,11 @@ mutation.
 When this API is used with a GitHub App token, the resulting commit will be signed and verified by
 GitHub on behalf of the application.
 
+*NOTE:* One limitation of creating commits using the GraphQL API is that it does not expose any
+mechanism to set or change file modes. It merely takes the file contents, base64 encoded. This means
+that if you rely on `commit-headless` to push binary files (or executable scripts), the file in the
+resulting commit will not retain that executable bit.
+
 [mutation]: https://docs.github.com/en/graphql/reference/mutations#createcommitonbranch
 [action-branch]: https://github.com/DataDog/commit-headless/tree/action
 

action-template/README.md

@@ -27,7 +27,14 @@ If your workflow creates multiple commits and you want to push all of them, you
     git add bot.txt && git commit -m"bot commit 2"
 
     # List both commit hashes in reverse order, space separated
-    echo "commits=\"$(git log "${{ github.sha }}".. --format='%H%x00' | tr '\n' ' ')\"" >> $GITHUB_OUTPUT
+    echo "commits=\"$(git log "${{ github.sha }}".. --format='%H' | tr '\n' ' ')\"" >> $GITHUB_OUTPUT
+
+    # If you just have a single commit, you can do something like:
+    #  echo "commit=$(git rev-parse HEAD)" >> $GITHUB_OUTPUT
+    # and then use it in the action via:
+    #  with:
+    #    ...
+    #    commits: ${{ steps.create-commits.outputs.commit }}
 
 - name: Push commits
   uses: DataDog/commit-headless@action/v%%VERSION%%