[llvm-branch-commits] [llvm] release/20.x: [libc++][ci] Update the Windows toolchains to Clang 19 (#129232) (PR #129303)

[Tom Stellard via llvm-branch-commits]

tstellar wrote:

Does this need to be in 20.1.0 or could it wait until 20.1.1 ?

https://github.com/llvm/llvm-project/pull/129303