[clang] [Clang][OpenMP] Fix the wrong transform of `num_teams` claused introduced in #99732 (PR #102716)

[Shilei Tian via cfe-commits]

shiltian wrote:

> > > A test is required
> > 
> > 
> > I literally don't know how to test this TBH. I think our current OpenMP tests generally don't cover this at all.
> 
> They do. To test this, you need to use clause in the template and check that template params successfully replaced upon instantiation.

Aha, good to know. Thanks. Will add tests.

https://github.com/llvm/llvm-project/pull/102716