Fix Coverage stage branch check for PR builds

Use CHANGE_BRANCH for PR builds (BRANCH_NAME is PR-3 in PR context)

Entire-Checkpoint: 7a9bf7a0810d

Jenkinsfile

@@ -106,7 +106,8 @@ pipeline {
     stage('Coverage') {
       when {
         expression {
-          return env.BRANCH_NAME ==~ /main|master|coverage.*|feature.*/
+          def branch = env.CHANGE_BRANCH ?: env.BRANCH_NAME
+          return branch ==~ /main|master|coverage.*|feature.*/
         }
       }
       steps {