fix: Update upgrade-python-requirements.yml

Author: Feanil Patel

.github/workflows/upgrade-python-requirements.yml

@@ -17,7 +17,7 @@ jobs:
     uses: openedx/.github/.github/workflows/upgrade-python-requirements.yml@master
     with:
     # If copying manually, also provide your default branch name in quotes here
-      branch: ${{ github.event.inputs.branch || "master" }}
+      branch: ${{ github.event.inputs.branch || 'master' }}
       # optional parameters below; fill in if you'd like github or email notifications
       user_reviewers: "feanil"
       # team_reviewers: ""