[clang] [Clang] Improve support for expression messages in `static_assert` (PR #73234)

[via cfe-commits]

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@@ -617,6 +617,9 @@ Bug Fixes in This Version
 - Fix crash during code generation of C++ coroutine initial suspend when the return
   type of await_resume is not trivially destructible.
   Fixes (`#63803 <https://github.com/llvm/llvm-project/issues/63803>`_)
+- Fix crash when the object used as a ``static_asssert`` message has ``size`` or ``data`` members
+  which are not member functions.
+- Support UDLs in ``static_asssert`` message.
----------------
oliverscherf-tomtom wrote:

```suggestion
- Fix crash when the object used as a ``static_assert`` message has ``size`` or ``data`` members
  which are not member functions.
- Support UDLs in ``static_assert`` message.
```

https://github.com/llvm/llvm-project/pull/73234