[clang] [llvm] [MC/DC][Coverage] Loosen the limit of NumConds from 6 (PR #82448)

[via llvm-commits]

zmodem wrote:

This broke the lit tests on mac: https://green.lab.llvm.org/job/llvm.org/job/clang-stage1-RA/1096/

I'll revert to green for now.

https://github.com/llvm/llvm-project/pull/82448