Fix PR Tester

http://jenkins2.bc.jonqe.lab.eng.bos.redhat.com:8080/job/kiali-core-pr-e2e-test/105/console

• The jenkins job was trying to install Oracle JDK:

Installing JDK jdk-8u172-oth-JPR
Downloading JDK from http://download.oracle.com/otn-pub/java/jdk/8u172-b11/a58eab1ec242421181065cdc37240b08/jdk-8u172-linux-x64.tar.gz
Building remotely on jenkins-slave-kiali-ui-tests-qq9b8 (kiali-ui-tests python) in workspace /home/jenkins/workspace/kiali-core-pr-e2e-test
Installing JDK jdk-8u172-oth-JPR
Downloading JDK from http://download.oracle.com/otn-pub/java/jdk/8u172-b11/a58eab1ec242421181065cdc37240b08/jdk-8u172-linux-x64.tar.gz
java.io.IOException: Failed to request http://download.oracle.com/otn-pub/java/jdk/8u172-b11/a58eab1ec242421181065cdc37240b08/jdk-8u172-linux-x64.tar.gz?AuthParam=1538122004_e8c60da919bb4485648975af0c36de98 exit code=404
at hudson.tools.JDKInstaller.locate(JDKInstaller.java:492)
at hudson.tools.JDKInstaller.performInstallation(JDKInstaller.java:150)
at hudson.tools.InstallerTranslator.getToolHome(InstallerTranslator.java:72)
at hudson.tools.ToolLocationNodeProperty.getToolHome(ToolLocationNodeProperty.java:109)
at hudson.tools.ToolInstallation.translateFor(ToolInstallation.java:206)
at hudson.model.JDK.forNode(JDK.java:148)
at hudson.model.AbstractProject.getEnvironment(AbstractProject.java:341)
at hudson.model.Run.getEnvironment(Run.java:2356)
at hudson.model.AbstractBuild.getEnvironment(AbstractBuild.java:886)
at hudson.plugins.git.GitSCM.checkout(GitSCM.java:1179)
at hudson.scm.SCM.checkout(SCM.java:504)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1208)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:574)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:499)
at hudson.model.Run.execute(Run.java:1798)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:429)