[jenkins] Make it possible to skip running packaged Xamarin.Mac tests by setting the 'skip-packaged-xamarin-mac-tests' label. (#9170)

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jenkins/Jenkinsfile

@@ -837,6 +837,11 @@ timestamps {
                             stage ("Package XM tests") {
                                 currentStage = "${STAGE_NAME}"
                                 echo ("Building on ${env.NODE_NAME}")
+                                def skipPackagedXamarinMacTests = getLabels ().contains ("skip-packaged-xamarin-mac-tests")
+                                if (skipPackagedXamarinMacTests) {
+                                    echo ("Skipping packaged Xamarin.Mac tests because the label 'skip-packaged-xamarin-mac-tests' was found")
+                                    hasXamarinMacTests = false
+                                } else {
                                     def exitCode = sh (script: "make -C ${workspace}/xamarin-macios/tests package-tests", returnStatus: true)
                                     if (exitCode != 0) {
                                         hasXamarinMacTests = false
@@ -848,6 +853,7 @@ timestamps {
                                             uploadFiles ("tests/*.7z", "wrench", virtualPath)
                                     }
                                 }
+                            }
 
                             timeout (time: 13, unit: 'HOURS') {
                                 // We run tests locally and on older macOS bots in parallel.