Fix cli help tests

compiler/testData/cli/js/jsExtraHelp.out

@@ -1,6 +1,7 @@
 Usage: kotlinc-js <options> <source files>
 where advanced options include:
   -Xno-inline                Disable method inlining
+  -Xplugin <path>            Load plugins from the given classpath
 
 Advanced options are non-standard and may be changed or removed without any notice.
 OK

compiler/testData/cli/js/jsHelp.out

@@ -13,4 +13,6 @@ where possible options include:
   -version                   Display compiler version
   -help (-h)                 Print a synopsis of standard options
   -X                         Print a synopsis of advanced options
+  -P plugin:<pluginId>:<optionName>=<value>
+                             Pass an option to a plugin
 OK