ci: GitHubCI - no need to just run in master branch (#3840)

When a contributor wants to create a PR for commitlint,
the normal thing for him to do first is fork the repo and
create a branch with a different name than master. Then,
if he pushes his commits, he should be able to see the CI
status of his fixes before he opens the PR.

Author: knocte

.github/workflows/CI.yml

@@ -3,7 +3,7 @@ name: CI
 on:
   push:
     branches:
-      - master
+      - '**'
   pull_request:
     types: [opened, synchronize]