Smoke Tester: Dont install groovy/expression plugins

Those two plugins are modules now and thus dont need to be installed
explicitely when testing.

dev-tools/smoke_test_rc.py

@@ -67,8 +67,6 @@ DEFAULT_PLUGINS = ["analysis-icu",
                    "discovery-ec2",
                    "discovery-gce",
                    "discovery-multicast",
-                   "lang-expression",
-                   "lang-groovy",
                    "lang-javascript",
                    "lang-plan-a",
                    "lang-python",