This is the version shipped in Fedora 38. As Fedora 38 is now out, the
core developers switch to it. Our gitlab-ci will also use that as base
image for the check-{patch.tree} tests and to generate the pages. There
is a need that everybody agrees on which clang-format version to use,
and that version should be the one of the currently used Fedora release.
Also update the used Fedora image in "contrib/scripts/nm-code-format-container.sh"
script.
The gitlab-ci still needs update in the following commit. This change
in isolation will break the "check-tree" test.
c275d24637