MM-52282 Remove ExperimentalSettings.PatchPluginsReactDOM (#23172)

* MM-52282 Remove ExperimentalSettings.PatchPluginsReactDOM

* Fix missing file from last commit

* Fix test usage of plugin.NewEnvironment

server/channels/web/web_test.go

@@ -283,7 +283,7 @@ func TestPublicFilesRequest(t *testing.T) {
 	defer os.RemoveAll(pluginDir)
 	defer os.RemoveAll(webappPluginDir)
 
-	env, err := plugin.NewEnvironment(th.NewPluginAPI, app.NewDriverImpl(th.Server), pluginDir, webappPluginDir, false, th.App.Log(), nil)
+	env, err := plugin.NewEnvironment(th.NewPluginAPI, app.NewDriverImpl(th.Server), pluginDir, webappPluginDir, th.App.Log(), nil)
 	require.NoError(t, err)
 
 	pluginID := "com.mattermost.sample"