cephadm: patch the `cephadm.logger` class

cephadm: patch the `cephadm.logger` class

Patch the logger class instead of globally mocking the class from within
the loaded source file. This was inadvertently allowing for the entire
test run to succeed, while a single run of a test case would fail due to
the missing mock.

For example:
    `tox -e py3 tests/test_cephadm.py::TestShell::test_fsid`

Fixes: Fixes: https://tracker.ceph.com/issues/57621
Signed-off-by: Michael Fritch <mfritch@suse.com>