here you go ( using the reproducer from Christian )
leap156:~ # uname -r
6.4.0-150600.1.g10a598f-default
leap156:~ # echo '/t { pivot_root "/tmp/" -> "/tmp/", }' | apparmor_parser -r
Warning from stdin (line 1): apparmor_parser: cannot use or update cache,
disable, or force-complain via stdin
Am I correct to assume that this is a success ?