Add a better error message for users of CodeQL CLI 2.7.2 and earlier

Improves the error message for users running (a) CLI 2.7.2 and earlier
and (b) `ubuntu-22.04`, to which `ubuntu-latest` is now being migrated.
Previously this was "undefined symbol: __libc_dlopen_mode, version
GLIBC_PRIVATE".
Now we give some guidance around glibc versions and using the
`ubuntu-20.04` runner image.

Author: henrymercer