Isolate the distributed cache key prefix per LanguageManagement test app #23068
BackRelated to abpframework/abp#26333
ExternalLocalizationSaver skips saving when its lock is taken, and the lock key only carries the cache key prefix, so test apps running at the same time skipped each other's saves (Should_Save_All_Localization_Resources saw 0 records). Each test app now gets its own prefix.