Remove unnecessary global re-definitions

Webpack supports having multiple DefinePlugins in the build, so we don't
need to worry about canceling out the affect of the other DefinePlugin
that's already provided by the shared webpack config.

apps/editing-toolkit/webpack.config.js

@@ -76,12 +76,7 @@ function getWebpackConfig( env = {}, argv = {} ) {
 				( plugin ) => plugin.constructor.name !== 'DependencyExtractionWebpackPlugin'
 			),
 			new webpack.DefinePlugin( {
-				'process.env.NODE_ENV': JSON.stringify( process.env.NODE_ENV ),
-				'process.env.FORCE_REDUCED_MOTION': JSON.stringify(
-					!! process.env.FORCE_REDUCED_MOTION || false
-				),
 				__i18n_text_domain__: JSON.stringify( 'full-site-editing' ),
-				global: 'window',
 			} ),
 			new DependencyExtractionWebpackPlugin( {
 				injectPolyfill: true,