feat(mvn): add completion for Vaadin (#11362)

plugins/mvn/mvn.plugin.zsh

@@ -283,6 +283,8 @@ function listMavenCompletions {
     toolchain:toolchain
     #liberty
     liberty:clean-server liberty:compile-jsp liberty:configure-arquillian liberty:create-server liberty:debug liberty:debug-server liberty:deploy liberty:dev liberty:display-url liberty:dump-server liberty:install-apps liberty:install-feature liberty:install-server liberty:java-dump-server liberty:package-server liberty:run liberty:run-server liberty:server-status liberty:start liberty:start-server liberty:status liberty:stop liberty:stop-server liberty:test-start-server liberty:test-stop-server liberty:undeploy liberty:uninstall-feature
+    # vaadin
+    vaadin:prepare-frontend vaadin:build-frontend vaadin:clean-frontend vaadin:dance
 
     # options
     "-Dmaven.test.skip=true" -DskipTests -DskipITs -Dmaven.surefire.debug -DenableCiProfile "-Dpmd.skip=true" "-Dcheckstyle.skip=true" "-Dtycho.mode=maven" "-Dmaven.test.failure.ignore=true" "-DgroupId=" "-DartifactId=" "-Dversion=" "-Dpackaging=jar" "-Dfile="