Minor fix to address ?: VC conformance improvement. (dotnet/coreclr#10208)

Minor fix to address ?: VC conformance improvement. (dotnet/coreclr#10208)

Visual C++ has made some conformance changes to conditional operator
that will be available under /permissive- and which make the inference of
result type of the conditional operator in these 2 places ambiguous. This
happens because the class type in one of the arguments provides both: the
constructor from and the conversion operator to T - LCWSTR here.

Commit migrated from https://github.com/dotnet/coreclr/commit/67f40646d76d914ab7f099df25768c73c4f55bad