[llvm] [libcxx] Add pre-commit hooks and git config for libc++ & git-clang-format. (PR #73798)

[Tobias Hieta via llvm-commits]

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@@ -0,0 +1,31 @@
+#!/bin/bash
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tru wrote:

No I think it's fine to start with libc++, but I think we should have the discussion and see if the rest of the community would like to follow libc++ here and have the commit hook for everyone. I think it's beneficial.

https://github.com/llvm/llvm-project/pull/73798