[lldb][DataFormatter] Fix libcxx std::deque formatter for references and pointers

[lldb][DataFormatter] Fix libcxx std::deque formatter for references and pointers

(Addresses GH#62153)

The `SBType` APIs to retrieve details about template arguments,
such as `GetTemplateArgumentType` or `GetTemplateArgumentKind`
don't "desugar" LValueReferences/RValueReferences or pointers.
So when we try to format a `std::deque&`, the python call to
`GetTemplateArgumentType` fails to get a type, leading to
an `element_size` of `0` and a division-by-zero python exception
(which gets caught by the summary provider silently). This leads
to the contents of such `std::deque&` to be printed incorrectly.

This patch dereferences the reference/pointer before calling
into the above SBAPIs.

**Testing**

* Add API test

Differential Revision: https://reviews.llvm.org/D148531