Add Password hardening CLI support

[davidpil2002]

What I did

Add Password Hardening CLI

How I did it

created the CLI by using YANG model generator, the YANG model can be found in the password hardening HLD https://github.com/Azure/SONiC/blob/master/doc/passw_hardening/hld_password_hardening.md#TestPlan
and also in sonic-buildimage will be merged in the path: src/sonic-yang-models/yang-models/sonic-passwh.yang

How to verify it

Manually:
you can use configurations command like"config passw-hardening policies " or
"show passw-hardening policies" (more examples in the HLD.)
Auto:
1.There are unitest of each policy including good & bad flow in this commit, that should pass.

2.There are tests in sonic-mgmt repo in the path: sonic-mgmt/tests/passw_hardening/
the test are end to end test and the are testing the config/show CLI commands as well.

Previous command output (if the output of a command-line utility has changed)

(new feature)

New command output (if the output of a command-line utility has changed)

root@r-panther-13:/home/admin# show passw-hardening policies
STATE    EXPIRATION    EXPIRATION WARNING    HISTORY    LEN MAX    LEN MIN    USERNAME PASSW MATCH    LOWER CLASS    UPPER CLASS    DIGITS CLASS    SPECIAL CLASS
-------  ------------  --------------------  ---------  ---------  ---------  ----------------------  -------------  -------------  --------------  ---------------
enabled      30           10                   4         100        30               false                 true            true            true          true

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: davidpil2002 (d3a90f6)

[liat-grozovik]

@liuh-80 please review and approve this PR now that it has the easycla issue fixed. the other one will be closed.

[liat-grozovik]

as the original was approved and this is one opened only due to easycla issue with the original, approving and merging.