Use release version of TestBench

pom.xml

@@ -56,7 +56,7 @@
         <sonar.issuesReport.html.enable>true</sonar.issuesReport.html.enable>
 
         <vaadin.icons.version>3.0.1</vaadin.icons.version>
-        <vaadin.testbench.version>5.0.0.beta5</vaadin.testbench.version>
+        <vaadin.testbench.version>5.0.0</vaadin.testbench.version>
     </properties>
 
     <!-- TODO: remove this after maven plugin has been released -->