[clang] [clang] accept member specializations declared in class scope (PR #207256)

[Matheus Izvekov via cfe-commits]

mizvekov wrote:

> There should be a test in the DR directory, the dr status page should be updated and the release note should mention the DR

Except none of the tests from the core issue mention member specializations at all, and I expected it only to include those.

Also, there would be no other update to the core issue on the Clang side, presumably because we still haven't fully implemented it, and there were no changes to the proposed resolution.

https://github.com/llvm/llvm-project/pull/207256