It is not part of any module, so it needs to be declared as such.

The existing `export-interfaces-{build,install}` tests were actually
doing this, but make those test exporting the interfaces and copy the
existing tests to tests which explicitly test the "no properties"
condition.

See: https://gitlab.kitware.com/cmake/cmake/-/issues/18355#note_1296721
See: https://github.com/ninja-build/ninja/pull/1937

Run the `clang-format.bash` script to update all our C and C++ code to a
new style defined by `.clang-format`.  Use `clang-format` version 15.

* If you reached this commit for a line in `git blame`, re-run the blame
  operation starting at the parent of this commit to see older history
  for the content.

* See the parent commit for instructions to rebase a change across this
  style transition commit.

Fixes: #24315

These patches now support the `-MF` output, so remove the `none` support
added just for the old patchset which did not use it.

Also update the flag name to `-fmodule-output=`.

Due to the new Clang module mapper flag, use a new experimental support
UUID as well.

2c558cfd1b gitlab-ci: add CI jobs for Clang with C++20 modules
abd42e9cfc ci: add a Docker container for clang support of C++20 modules
51093f3002 Clang-FindBinUtils: also find `clang-scan-deps`
0b333de923 ci: add C++ module rules file for Clang
21b9fb1e8c cmCxxModuleMapper: support the `clang` module map format
9c66224668 cmNinjaTargetGenerator: skip setting `depfile` for `none` scantypes
9123a0991f cmNinjaTargetGenerator: use `.clear()` to empty out some strings

Acked-by: Kitware Robot <kwrobot@kitware.com>
Acked-by: Cristian Adam <cristian.adam@gmail.com>
Merge-request: !7978

Visual Studio support warrants a new ID.

Visual Studio does not currently have a place to insert the logic
required to implement this test, so skip it if possible.