[lldb] Add SubstTemplateTypeParm to RemoveWrappingTypes

Like the other type sugar removed by RemoveWrappingTypes, SubstTemplateTypeParm
is just pure sugar that should be ignored. If we don't ignore it (as we do now),
LLDB will fail to read values from record fields that have a
SubstTemplateTypeParm type.

Only way to produce such a type in LLDB is to either use the `import-std-module`
setting to get a template into the expression parser or just create your own
template directly in the expression parser which is what we do in the test.

Reviewed By: jarin

Differential Revision: https://reviews.llvm.org/D85132