update integration test yml

Author: muzahidul-opti

.github/workflows/integration_tests.yml

@@ -18,7 +18,7 @@ jobs:
         token: ${{ secrets.CI_USER_TOKEN }}
         repository: 'optimizely/ci-helper-tools'
         path: 'home/runner/ci-helper-tools'
-        ref: 'remove-travis'
+        ref: 'master'
     - name: set SDK Branch if PR
       env: 
         HEAD_REF: ${{ github.head_ref }}