[clang] [clang-repl] Don't check printf output order in pretty-print.cpp (PR #228349)

[Vassil Vassilev via cfe-commits]

https://github.com/vgvassilev approved this pull request.

LGTM as a quick fix. I believe when printf outputs on stdout the OS flushes the buffer at its choice and we should not rely on that for clang-repl but flush after executing each line. I suspect we need to probably track this as an issue or provide a fix for it.

https://github.com/llvm/llvm-project/pull/228349