Work around libstdc++ issue [PR101510] with create_directories where the
leaf already exists as a symlink. Fixes #24257, introduced by the switch
to `std::filesystem`. It is meant to be more thorough than #24266, which
only worked around one instance of the problem.
The issue was fixed upstream in
https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=124eaa50e0a34f5f89572c1aa812c50979da58fc,
but unfortunately we'll have to carry a fix for it for a while.
This introduces a function `fs::create_directories` which wraps
`std::filesystem::create_directories`. This allows easiliy reverting the
workaround when it is no longer necessary.
This is a backport of core#24338
Depends on D13730