fix return type of LangageServiceHost.resolve*
fix return type of LangageServiceHost.resolve*

Fixes: #28058

kitsonk/TypeScript,weswigham/TypeScript,nojvek/TypeScript,nojvek/TypeScript,alexeagle/TypeScript,weswigham/TypeScript,SaschaNaz/TypeScript,Microsoft/TypeScript,SaschaNaz/TypeScript,minestarks/TypeScript,SaschaNaz/TypeScript,SaschaNaz/TypeScript,kpreisser/TypeScript,kitsonk/TypeScript,donaldpipowitch/TypeScript,kpreisser/TypeScript,kitsonk/TypeScript,RyanCavanaugh/TypeScript,minestarks/TypeScript,Microsoft/TypeScript,donaldpipowitch/TypeScript,minestarks/TypeScript,Microsoft/TypeScript,donaldpipowitch/TypeScript,RyanCavanaugh/TypeScript,kpreisser/TypeScript,weswigham/TypeScript,nojvek/TypeScript,alexeagle/TypeScript,microsoft/TypeScript,nojvek/TypeScript,donaldpipowitch/TypeScript,microsoft/TypeScript,RyanCavanaugh/TypeScript,alexeagle/TypeScript,microsoft/TypeScript