updating branch name

Author: spa5k

.github/workflows/ci.yml

@@ -1,7 +1,7 @@
 name: CI
 on:
   pull_request:
-    branches: [master]
+    branches: [main]
     types: [opened, reopened, synchronize]
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}