Always get diagnostics when emitting irrespective of whether its declaration only emit

The diagnostics reporting and expression resolution caching is quite intermingled at present.
Hence when we tried to get the declaration output without getting diagnostics, the resolution for functions return expression is cached but errors arent reported
Symbols arent marked as referenced. So at later time when trying to get the diagnostics since the expression resolution is cached, it doesnt even go through all checks
For now get diagnostics irrespective of declaration only output to avoid this issue.
Fixes #21518

src/compiler/program.ts

@@ -1179,7 +1179,7 @@ namespace ts {
             // This is because in the -out scenario all files need to be emitted, and therefore all
             // files need to be type checked. And the way to specify that all files need to be type
             // checked is to not pass the file to getEmitResolver.
-            const emitResolver = getDiagnosticsProducingTypeChecker().getEmitResolver((options.outFile || options.out) ? undefined : sourceFile, cancellationToken, emitOnlyDtsFiles);
+            const emitResolver = getDiagnosticsProducingTypeChecker().getEmitResolver((options.outFile || options.out) ? undefined : sourceFile, cancellationToken);
 
             performance.mark("beforeEmit");