build(ci): Add conventional commit title check (facebookincubator#11520)

Summary:
Check the PR title against cc pattern added  in facebookincubator#11356. Fails with a pointer to  CONTRIBUTING.md.
We are running the title change on every commit as it takes under 5 seconds to run and this way we avoid weird states with skipped checks overriding failed results when the title was triggered outside of a commit.

We could add a comment to the PR but that would require a workflow with elevated permissions using `pull_request_target` which should be avoided if possible. So I think the marginally lower ux is justified, we still get a marker/reminder for reviewers through this job.

Pull Request resolved: facebookincubator#11520

Reviewed By: pedroerp

Differential Revision: D65947963

Pulled By: Yuhta

fbshipit-source-id: 290b97f784011367d3e481ff49f42b7da65fdf7a

Author: assignUser

.github/workflows/preliminary_checks.yml

@@ -15,6 +15,11 @@ name: Run Checks
 
 on:
   pull_request:
+    types:
+      - opened
+      - reopened
+      - edited
+      - synchronize
 
 permissions:
   contents: read
@@ -70,3 +75,23 @@ jobs:
             echo "\`\`\`" >> $GITHUB_STEP_SUMMARY
             exit 1
           fi
+
+  title-check:
+    name: PR Title Format
+    runs-on: ubuntu-latest
+    steps:
+      - shell: python
+        env:
+          title: "${{ github.event.pull_request.title }}"
+        run: |
+          import re
+          import os
+          title = os.environ["title"]
+          title_re = r"^(feat|fix|build|test|docs|refactor|misc)(\(.+\))?!?: ([A-Z].+)[^.]$"
+          match = re.search(title_re, title)
+
+          if match is None:
+            print("::error::Please follow conventional commit guidelines in commit titles as described in CONTRIBUTING.md: https://github.com/facebookincubator/velox/blob/main/CONTRIBUTING.md#commit-messages")
+            exit(1)
+          else:
+            exit(0)