chore: Require semantic comments on PR titles. (#9459)

### Description

We're looking to use semantic titles for PRs so that they release notes
look a little tidier. This action will enforce this for us.

.github/workflows/semantic-release.yml

@@ -0,0 +1,33 @@
+name: Lint pull request title
+
+on:
+  pull_request_target:
+    types:
+      - opened
+      - edited
+      - synchronize
+      - reopened
+
+permissions:
+  pull-requests: read
+
+jobs:
+  main:
+    name: Validate PR title
+    runs-on: ubuntu-latest
+    steps:
+      - uses: amannn/action-semantic-pull-request
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          # Configure that a scope must always be provided.
+          requireScope: false
+          # Configure additional validation for the subject based on a regex.
+          # Ensures that the subject doesn't start with an uppercase character.
+          subjectPattern: ^[A-Z].*$
+          # If `subjectPattern` is configured, you can use this property to override
+          # the default error message that is shown when the pattern doesn't match.
+          # The variables `subject` and `title` can be used within the message.
+          subjectPatternError: |
+            The subject "{subject}" found in the pull request title "{title}" doesn't match the configured pattern.
+            Please ensure that the subject doesn't start with a lowercase character.