Merge PR #40924 into master

* refs/pull/40924/head:
	mgr/cephadm: check hostname resolution before adding host
	cephadm: provide a way to checkhost connection without /etc/hosts passed the shell
	doc/cephadm: remove /etc/hosts from list of hostname resoltion methods

Reviewed-by: Sage Weil <sage@redhat.com>
Reviewed-by: Adam King <adking@redhat.com>

diff --cc doc/cephadm/host-management.rst
Simple merge

diff --cc src/cephadm/cephadm
Simple merge

diff --cc src/pybind/mgr/cephadm/module.py
Simple merge

diff --cc src/pybind/mgr/cephadm/serve.py
Simple merge