chore: pull request build on PR opened event (#7360)

Author: kuhe

.github/workflows/pull-request-build.yml

@@ -1,7 +1,7 @@
 name: Build SDK
 on:
   pull_request:
-    types: [synchronize, ready_for_review]
+    types: [opened, synchronize, ready_for_review]
 
 concurrency:
   group: start-pull-request-build-${{ github.ref }}