Dev cli sessions

[i-davydenko]

sonic-net/SONiC#1367
i-davydenko/sonic-host-services#1

Why I did it
Give ability to:

configure limit for active login sessions.
configure ssh-server / serial console autologout timeout
configure sysrq-capabilities (enable / disable)
Work item tracking
Microsoft ADO (number only):
How I did it
Add new service that responsible for serial configuration;
Update existing flows for extended ssh-server configurations in hostcfgd;
Add YANG model to support new configuration.

How to verify it
Which release branch to backport (provide reason below if selected)
201811
201911
202006
202012
202106
202111
202205
202211
202305
Tested branch (Please provide the tested image version)

Description for the changelog
Link to config_db schema for YANG module changes
ssh_server
serial_console

A picture of a cute animal (not mandatory but encouraged)

[linux-foundation-easycla]

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