Use hash of updated lock files in branch name

This prevents the workflow failing when the previous branch hasn't
been merged. It was finding the branch already existed on the
remote and failing.

.github/workflows/conda-lock.yml

@@ -36,7 +36,7 @@ jobs:
         run: |
           git config --local user.name "$GITHUB_ACTOR"
           git config --local user.email "[email protected]"
-          git switch -c "conda-lock-$(sha256sum ${{ runner.temp }}/lock_file_hashes | head -c 8)"
+          git switch -c "conda-lock-files"
           tox -e py39-lock,py310-lock,py311-lock
 
       - name: Create pull requests
@@ -47,9 +47,10 @@ jobs:
             echo "Lock files unchanged. Skipping pull request..."
             exit 0
           fi
+          # Update lock_file_hashes so pushed branch name is unique.
+          sha256sum requirements/* > ${{ runner.temp }}/lock_file_hashes
           git add requirements/locks/*.txt
           git commit -m "[CI] Update conda lock files"
-          git push --set-upstream origin "conda-lock-$(sha256sum ${{ runner.temp }}/lock_file_hashes | head -c 8)"
+          git push --set-upstream origin "conda-lock-files:conda-lock-$(sha256sum ${{ runner.temp }}/lock_file_hashes | head -c 8)"
           # Create PR on GitHub using GitHub CLI.
-          gh pr create --base main --title "[CI] Update conda lock files" \
-          --body "Created automatically by GitHub Actions."
+          gh pr create --base main --title "[CI] Update conda lock files" --body "Created automatically by GitHub Actions."