Revert "add main build trigger for testing"

This reverts commit ffc0984.

Author: ezhang6811

.github/workflows/main-build.yml

@@ -4,7 +4,6 @@ on:
     branches:
       - main
       - "release/v*"
-      - "fix-e2e-test"
   workflow_dispatch: # be able to run the workflow on demand
 env:
   AWS_DEFAULT_REGION: us-east-1