add pool service controller.

[zyjhtangtang]

What type of PR is this?

/kind feature
/sig network

What this PR does / why we need it:

The first-level controller for the multi-region load balancer.

Does this PR introduce a user-facing change?

YES

[codecov]

Codecov Report

Attention: Patch coverage is 73.75000% with 147 lines in your changes are missing coverage. Please review.

Project coverage is 55.24%. Comparing base (839a52a) to head (1df5657).
Report is 1 commits behind head on master.

Files	Patch %	Lines
...rset/loadbalancerset/loadbalancerset_controller.go	65.88%	60 Missing and 27 partials ⚠️
...oller/loadbalancerset/loadbalancerset/predicate.go	75.38%	16 Missing and 16 partials ⚠️
...ler/loadbalancerset/loadbalancerset/annotations.go	79.48%	8 Missing and 8 partials ⚠️
...r/loadbalancerset/loadbalancerset/event_handler.go	83.56%	9 Missing and 3 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2010      +/-   ##
==========================================
+ Coverage   54.71%   55.24%   +0.53%     
==========================================
  Files         177      183       +6     
  Lines       17271    17831     +560     
==========================================
+ Hits         9450     9851     +401     
- Misses       6849     6953     +104     
- Partials      972     1027      +55     

Flag	Coverage Δ
unittests	55.24% <73.75%> (+0.53%)	⬆️

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[zyjhtangtang]

/rerun

[rambohe-ch]

@zyjhtangtang I think the repo of controllers about MultiPoolLoadBalancer should be constructed as following:

controller:
|
-- loadbalancerset:
   |
   -- loadbalancerset:
   |
   -- enslb:
   | 
   -- viplb:

[zyjhtangtang]

@zyjhtangtang I think the repo of controllers about MultiPoolLoadBalancer should be constructed as following:

controller:
|
-- loadbalancerset:
   |
   -- loadbalancerset:
   |
   -- enslb:
   | 
   -- viplb:

Thanks for the suggestion, I have adjusted the relevant directory structure

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[rambohe-ch]

/lgtm