Uniform etcd and etcdctl snapshot TLS related options

[sellisd]

As of etcd version v3.5.10 when I want to take a snapsot I can provide the following global options --cacert, --cert and --key (./etcdctl snapshot --help). However when starting an etcd server the equivalent options are different (e.g. --trusted-ca-file, --cert-file, --key-file). As a new user I find this confusing and unless I am missing something it should be relatively easy to fix?