ci: attempt to pass branch name as var to codepipeline

Author: necipallef

.github/workflows/e2e_test_for_prs.yml

@@ -19,15 +19,12 @@ jobs:
         uses: aws-actions/configure-aws-credentials@e3dd6a429d7300a6a4c196c26e071d42e0343502 #v4.0.2
         with:
           role-to-assume: ${{secrets.AWS_E2E_ROLE_ARN}}
-          aws-region: ${{secrets.AWS_E2E_REGION}}
+          aws-region: ${{vars.AWS_E2E_REGION}}
       - name: Trigger AWS CodePipeline
         run: |
-          codepipeline_execution_id=$(aws codepipeline start-pipeline-execution --name ${{vars.AWS_E2E_TOPIC_BRANCH_CODEPIPELINE_NAME}} --query 'pipelineExecutionId' --output text)
+          codepipeline_execution_id=$(aws codepipeline start-pipeline-execution --name ${{vars.AWS_E2E_TOPIC_BRANCH_CODEPIPELINE_NAME}} --variables name=BRANCH_NAME,value=${{github.head_ref}} --query 'pipelineExecutionId' --output text)
           echo "Pipeline execution ID: $codepipeline_execution_id"
           echo "codepipeline_execution_id=$codepipeline_execution_id" >> $GITHUB_ENV
-          echo ${{github.head_ref}}
-        env:
-          BRANCH_NAME: ${{github.head_ref}}
       - name: Poll Pipeline Status
         id: poll-status
         run: |