ci: Fix integration test pipeline not starting if there were 404ing C…

…I pipeline runs in the source branch (#6966)

.github/workflows/integration_tests.yml

@@ -155,7 +155,7 @@ jobs:
               -H "Authorization: token $GITHUB_TOKEN" \
               "api.github.com/repos/$REPO_SLUG/actions/workflows/CI.yml/runs?branch=$BRANCH" | \
             jq '[.workflow_runs[] | select(
-              (.head_commit.author.name | endswith("[bot]") | not ) and ( .conclusion == "success" ) 
+              (.head_commit != null) and (.head_commit.author.name | endswith("[bot]") | not ) and ( .conclusion == "success" ) 
             )][0] | .id')
           echo "Run ID that will be used to download artifacts from: $RUN_ID"
           echo "::set-output name=RUN_ID::$RUN_ID"