Update peter-evans/create-pull-request (#8039)

Updates `peter-evans/create-pull-request` to `v8.1.0`. This is *not* the
latest version, which was released days ago, but instead is an easier to
trust version from January with high usage.

Previous version was broken due to our update of the `checkout` action,
which broke the two actions we have that use `create-pull-request`, both
in our release process.

Long term, this action is a candidate to remove and replace with the
GitHub command line tooling.

Author: emilypgoogle

.github/workflows/create_releases.yml

@@ -53,7 +53,7 @@ jobs:
           INPUTS_PAST_NAME: ${{ inputs.past-name }}
 
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@271a8d0340265f705b14b6d32b9829c1cb33d45e # v7.0.8
+        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0 # v8.1.0
         with:
           base: 'releases/${{ inputs.name }}'
           branch: 'releases/${{ inputs.name }}.release'

.github/workflows/post_release_cleanup.yml

@@ -31,7 +31,7 @@ jobs:
           ./gradlew spotlessApply
 
       - name: Create Pull Request
-        uses: peter-evans/create-pull-request@271a8d0340265f705b14b6d32b9829c1cb33d45e # v7.0.8
+        uses: peter-evans/create-pull-request@c0f553fe549906ede9cf27b5156039d195d2ece0 # v8.1.0
         with:
           token: ${{ secrets.GOOGLE_OSS_BOT_TOKEN }}
           committer: google-oss-bot <firebase-oss-bot@google.com>