Improve unit-test for subnet service

[wenqiq]

Improve unit-test for Subnet service
Improve the log of the Subnet/SubnetSet controller

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 31.81818% with 15 lines in your changes missing coverage. Please review.

Project coverage is 64.91%. Comparing base (4246c65) to head (8d135ec).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/nsx/services/subnet/subnet.go	20.00%	12 Missing ⚠️
pkg/controllers/subnet/subnet_controller.go	25.00%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #850      +/-   ##
==========================================
+ Coverage   64.52%   64.91%   +0.38%     
==========================================
  Files          96       96              
  Lines       15153    15125      -28     
==========================================
+ Hits         9778     9818      +40     
+ Misses       4676     4607      -69     
- Partials      699      700       +1     

Flag	Coverage Δ
unit-tests	64.91% <31.81%> (+0.38%)	⬆️

Files with missing lines	Coverage Δ
pkg/controllers/subnetset/subnetset_controller.go	78.81% <100.00%> (-1.19%)	⬇️
pkg/controllers/subnet/subnet_controller.go	76.00% <25.00%> (-0.77%)	⬇️
pkg/nsx/services/subnet/subnet.go	37.95% <20.00%> (+12.26%)	⬆️

... and 1 file with indirect coverage changes