refactor: update Jenkinsfile for improved readability and consistency

Jenkinsfile

@@ -1,4 +1,4 @@
-region='us-central1-a'
+region="us-central1-a"
 testUrlPrefix="https://percona-jenkins-artifactory-public.s3.amazonaws.com/cloud-pxc-operator"
 tests=[]
 
@@ -14,7 +14,7 @@ void createCluster(String CLUSTER_SUFFIX) {
                 gcloud config set project $GCP_PROJECT
                 gcloud container clusters list --filter $CLUSTER_NAME-${CLUSTER_SUFFIX} --zone $region --format='csv[no-heading](name)' | xargs gcloud container clusters delete --zone $region --quiet || true
 
-                gcloud container clusters create --zone $region $CLUSTER_NAME-${CLUSTER_SUFFIX} --cluster-version=1.28 --machine-type=n1-standard-4 --preemptible --disk-size 30 --num-nodes=\$NODES_NUM --network=jenkins-vpc --subnetwork=jenkins-${CLUSTER_SUFFIX} --no-enable-autoupgrade --cluster-ipv4-cidr=/21 --labels delete-cluster-after-hours=6 && \
+                gcloud container clusters create --zone $region $CLUSTER_NAME-${CLUSTER_SUFFIX} --cluster-version=1.28 --machine-type=n1-standard-4 --preemptible --disk-size 30 --num-nodes=\$NODES_NUM --network=jenkins-vpc --subnetwork=jenkins-${CLUSTER_SUFFIX} --no-enable-autoupgrade --cluster-ipv4-cidr=/21 --labels delete-cluster-after-hours=6 --enable-ip-alias&& \
                 kubectl create clusterrolebinding cluster-admin-binding --clusterrole cluster-admin --user jenkins@"$GCP_PROJECT".iam.gserviceaccount.com || ret_val=\$?
                 if [ \${ret_val} -eq 0 ]; then break; fi
                 ret_num=\$((ret_num + 1))
@@ -150,17 +150,17 @@ void printKubernetesStatus(String LOCATION, String CLUSTER_SUFFIX) {
     """
 }
 
-TestsReport = '| Test name  | Status |\r\n| ------------- | ------------- |'
+TestsReport = '| Test name | Status |\r\n| ------------- | ------------- |'
 TestsReportXML = '<testsuite name=\\"PXC\\">\n'
 
 void makeReport() {
     def wholeTestAmount=tests.size()
     def startedTestAmount = 0
 
     for (int i=0; i<tests.size(); i++) {
+        def testNameWithMysqlVersion = tests[i]["name"] +"-"+ tests[i]["mysql_ver"].replace(".", "-")
         def testResult = tests[i]["result"]
         def testTime = tests[i]["time"]
-        def testNameWithMysqlVersion = tests[i]["name"] +"-"+ tests[i]["mysql_ver"].replace(".", "-")
         def testUrl = "${testUrlPrefix}/${env.GIT_BRANCH}/${env.GIT_SHORT_COMMIT}/${testNameWithMysqlVersion}.log"
 
         if (tests[i]["result"] != "skipped") {