fix: pin @bazel/karma karma dep to ~4.1.0 as 4.2.0 breaks stack trace…

…s in karma output

This fix is transitional as karma and the karma plugins required by @bazel/karma should be peerDependencies. This regression with karma 4.2.0 didn't have coverage as the yarn.lock file of /e2e/karma_stack_trace was not being updated and it was pulling in an old version of karma.

packages/karma/src/package.json

@@ -22,7 +22,7 @@
   },
   "dependencies": {
     "jasmine-core": "2.8.0",
-    "karma": "^4.0.0",
+    "karma": "~4.1.0",
     "karma-chrome-launcher": "2.2.0",
     "karma-firefox-launcher": "1.1.0",
     "karma-jasmine": "2.0.1",