[clang] [clang-repl] [test] Make an XFAIL more precise (PR #70991)

[Martin Storsjö via cfe-commits]

mstorsjo wrote:

> If you still need help reproducing or debugging the issue on our bot, please let me know.

Thanks, much appreciated. Can you test if https://github.com/mstorsjo/llvm-project/commit/clang-repl-xfail seems to run correctly in this environment? Otherwise I'll try to push it tomorrow and see how it fares on the bot.

https://github.com/llvm/llvm-project/pull/70991