Initialize the HNAS driver

[guankc]

Initialize the HNAS driver and
New SSH method to simulate shell execution (hnAS driver call interface required)

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

Release note:

[codecov]

Codecov Report

Merging #277 (187d3a3) into hnas_init (6ad2d83) will decrease coverage by 0.09%.
The diff coverage is 71.74%.

@@              Coverage Diff              @@
##           hnas_init     #277      +/-   ##
=============================================
- Coverage      70.55%   70.45%   -0.10%     
=============================================
  Files            163      166       +3     
  Lines          15798    16490     +692     
  Branches        1946     2068     +122     
=============================================
+ Hits           11146    11618     +472     
- Misses          3994     4171     +177     
- Partials         658      701      +43     

Impacted Files	Coverage Δ
delfin/drivers/utils/ssh_client.py	16.95% <5.88%> (-1.93%)	⬇️
delfin/drivers/hitachi/hnas/nas_handler.py	73.34% <73.34%> (ø)
delfin/drivers/hitachi/hnas/hds_nas.py	85.41% <85.41%> (ø)
delfin/drivers/hitachi/hnas/constants.py	100.00% <100.00%> (ø)
...dulers/telemetry/performance_collection_handler.py	92.85% <0.00%> (-7.15%)	⬇️
delfin/drivers/dell_emc/unity/unity.py	68.42% <0.00%> (-3.90%)	⬇️
...ager/scheduler/schedulers/telemetry/job_handler.py	68.38% <0.00%> (-2.95%)	⬇️
delfin/drivers/dell_emc/unity/alert_handler.py	81.48% <0.00%> (-2.07%)	⬇️
delfin/drivers/dell_emc/unity/rest_handler.py	48.85% <0.00%> (-1.15%)	⬇️
delfin/drivers/fake_storage/__init__.py	94.79% <0.00%> (-0.83%)	⬇️
... and 6 more