Remove direct dependency on babel-loader

The extension Webpack config does not use `babel-loader`, so we can
remove it as a direct dependency. `babel-loader` is still included in
our `node_modules` because Storybook depends on it, but the version is
now completely managed by Storybook rather than us.

Author: koesie10

extensions/ql-vscode/package-lock.json

@@ -1069,7 +1069,7 @@
         {
           "command": "codeQL.viewCfgContextEditor",
           "when": "false"
-        }, 
+        },
         {
           "command": "codeQLVariantAnalysisRepositories.openConfigFile",
           "when": "false"
@@ -1498,7 +1498,6 @@
     "@vscode/vsce": "^2.15.0",
     "ansi-colors": "^4.1.1",
     "applicationinsights": "^2.3.5",
-    "babel-loader": "^8.2.5",
     "cross-env": "^7.0.3",
     "css-loader": "~3.1.0",
     "del": "^6.0.0",