Add tag/branch name to build step

This exposes the name of the branch or tag that the Build Loop step is running. This helps show users what is being built (and thus a history) in the GitHub Actions view.

.github/workflows/build_loop.yml

@@ -1,5 +1,5 @@
 name: 4. Build Loop
-run-name: Build Loop
+run-name: Build Loop ${{ github.ref_name }}
 on:
   workflow_dispatch: