rollback karma-webpack to 4.0.0-rc.3

There seems to be a regression with the colors property in stats merging
to the default karma-webpack config. The fix for rc5 is here:
codymikol/karma-webpack#376 but it returned in
4.0.2 it seems.

Rather than fix this we should wait til we move to webpack v5 and
karma-webpack v5 which won't have this issue ideally.

config/karma.conf.js

@@ -104,10 +104,7 @@ export function getKarmaConfig(karma : Karma, cfg : Config) : KarmaConfig {
 
         basePath: __dirname,
 
-        frameworks: [
-            'mocha',
-            'webpack'
-        ],
+        frameworks: [ 'mocha' ],
 
         client: {
             captureConsole,

package.json

@@ -1,6 +1,6 @@
 {
   "name": "grumbler-scripts",
-  "version": "4.0.0-beta.5",
+  "version": "4.0.0-beta.8",
   "description": "Javascript module template.",
   "main": "index.js",
   "scripts": {
@@ -123,7 +123,7 @@
     "karma-sinon-chai": "^2.0.2",
     "karma-sourcemap-loader": "^0.3.7",
     "karma-spec-reporter": "0.0.32",
-    "karma-webpack": "4.0.2",
+    "karma-webpack": "4.0.0-rc.3",
     "mocha": "^9.1.3",
     "node-cleanup": "^2.1.2",
     "node-sass": "^4.13.1",