Make the github workflow run for all branches

.github/workflows/main.yaml

@@ -3,12 +3,6 @@ name: "Validate Conformance Test Syntax"
 on:
   push:
   pull_request:
-    branches:
-      # Branches from forks have the form 'user:branch-name' so we only run this job on pull_request events for
-      # branches that look like fork branches. Without this we would end up running this job twice for non-forked
-      # PRs, once for the push and then once for opening the PR.
-      # Taken from https://github.community/t/how-to-trigger-an-action-on-push-or-pull-request-but-not-both/16662/10
-      - '**:**'
 
 jobs:
   check-conformance-test-syntax: