Toolkit: Fix compilation loop when watching plugins for changes (#58167)

* fix(toolkit): ignore node_modules and dist directories when watching for changes to plugin

* fix(toolkit): move watchOptions.ignored config to pluginDev watch call

packages/grafana-toolkit/src/cli/tasks/plugin/bundle.ts

@@ -22,9 +22,8 @@ export const bundlePlugin = async ({ watch, production, preserveConsole }: Plugi
   const webpackPromise = new Promise<void>((resolve, reject) => {
     if (watch) {
       console.log('Started watching plugin for changes...');
-      compiler.watch({}, (err, stats) => {});
+      compiler.watch({ ignored: ['**/node_modules', '**/dist'] }, (err, stats) => {});
 
-      // @ts-ignore
       compiler.hooks.invalid.tap('invalid', () => {
         clearConsole();
         console.log('Compiling...');

packages/grafana-toolkit/src/config/webpack.plugin.config.ts

@@ -162,7 +162,6 @@ const getBaseWebpackConfig: WebpackConfigurationGetter = async (options) => {
       libraryTarget: 'amd',
       publicPath: '/',
     },
-
     performance: { hints: false },
     externals: [
       'lodash',