Fix README.md issue

[charlescordialDevExpress]

Fix README.md issue

[DevExpressExampleBot]

Please correct the project and update this pull request by pushing a new commit.

[PREPARATION ERROR]
	ERROR: 
Unhandled Exception: System.Reflection.ReflectionTypeLoadException: Unable to load one or more of the requested types. Retrieve the LoaderExceptions property for more information.
   at System.Reflection.RuntimeModule.GetTypes(RuntimeModule module)
   at System.Reflection.RuntimeModule.GetTypes()
   at System.Reflection.Assembly.GetTypes()
   at DevExpress.ProjectUpgrade.RegexHelp.MethodRegexBuilder.GetBuilderFactory(ELanguage language)
   at DevExpress.ProjectUpgrade.Updaters.XAFAddGlobalFeatureToggleWithBuilder..ctor(String updaterVersion)
   at DevExpress.ProjectUpgrade.GarbageAdder.Execute(FileUpdaterCollection fileUpdaters, ConversionParameters args, IFileSystem fileSystem)
   at DevExpress.ProjectUpgrade.FileProcessor..ctor(ConversionParameters args, IFileSystem fileSystem, IFileStateUserController fileStateUserController)
   at DevExpress.ProjectUpgrade.Program.Main(String[] args)
	OUTPUT: Project Converter (25.2.2.0)
The conversion is started

https://codecentralfarm.devexpress.devx/job/devextreme-dropdownbox-filter-data-in-nested-widget_25.1.3+/17/console