mkosi: update mkosi ref to 215a9497ccc089ba030da39e15e9e2371efad3cb (#40573)

* 215a9497cc fedora: Use N-1 key as well when querying rawhide GPG key
* 842a37ed6c Add MakeScriptsExecutable= setting to optionally try to
make scripts executable before bailing out
* 814f2004bb build(deps): bump github/codeql-action from 4.31.9 to
4.32.0
* d8f4f628bf build(deps): bump actions/checkout from 6.0.1 to 6.0.2
* 3e55361142 docs: remove superfluous definition colon
* 5901524c48 mkosi-tools: add libarchive-tools package.
* 968392f1b9 docs: Add information about gui mkosi-tools profile
* 0e2960c245 Add missing call to run_locale_gen()
* 41cd2067bc rpm: Set pkgverify_level to digest
* 86fe0f448a dnf: Give advanced users some control over plugins
* 50a1feee52 run: Improve sandbox command logging
* b1dffe1c3c Fix environment variable name for systemd-repart
* 07726068d9 Allow specifying "default" value for Initrds=
* 704f163ec0 Allow setting PORTABLE_PREFIXES= via Environment=
* e6588afb45 opensuse: More GPG key handling fixes
* c367f993dd opensuse: Fetch remote keys as well if RepositoryKeyFetch=
is enabled
* 31852c9314 ci: Use mkosi box for unit test CI as well
* e4229f5bf5 Make sure we pass the right context to
finalize_default_initrd()
* 9b431b783a tools: don't pull in virtiofsd in bookworm tools trees
* ae2d88d463 build(deps): bump github/codeql-action from 4.31.6 to
4.31.9
* 933401a8b6 build(deps): bump actions/checkout from 6.0.0 to 6.0.1
* 6bfeb4ac86 opensuse: Import GPG keys for all repositories
* 9829b9136f Add support for locale-gen
* 63ae86ec04 nixos: Use repository key fetching by default on nixos
* f01ca9904b docs: Reword dependencies vs tools tree requirement a bit
* ab47ba25ef docs: Minor correction on enabling unprivileged namespaces
* 7bd46a417e docs: Update unprivileged user namespace docs