feat: set transform to strip managedfields for informer

[vie-serendipity]

What type of PR is this?

Uncomment only one /kind <> line, hit enter to put that in a new line, and remove leading whitespace from that line:
/kind bug
/kind documentation
/kind enhancement
/kind good-first-issue
/kind feature
/kind question
/kind design
/sig ai
/sig iot
/sig network
/sig storage

/kind feature

What this PR does / why we need it:

Reduce memory of yurt-manager and yurthub by stripping managedfields of objects. Because managed fields are often quite large, taking up around 30%. We usually don't need them, so we can strip them for memory efficiency.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

NONE

other Note

[codecov]

Codecov Report

Attention: Patch coverage is 42.10526% with 11 lines in your changes missing coverage. Please review.

Project coverage is 58.97%. Comparing base (3713163) to head (1607a72).
Report is 40 commits behind head on master.

Files with missing lines	Patch %	Lines
cmd/yurthub/app/config/config.go	57.14%	6 Missing ⚠️
pkg/util/util.go	0.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2149      +/-   ##
==========================================
+ Coverage   56.09%   58.97%   +2.87%     
==========================================
  Files         186      211      +25     
  Lines       18092    19026     +934     
==========================================
+ Hits        10149    11220    +1071     
+ Misses       6910     6721     -189     
- Partials     1033     1085      +52     

Flag	Coverage Δ
unittests	58.97% <42.10%> (+2.87%)	⬆️

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[rambohe-ch]

@vie-serendipity Thank you for posting this pull request. I think it is very useful to reduce the RAM cost for yurt-manager and yurthub component. but serviceInformer is missed to SetTransform in the following place:

openyurt/pkg/yurthub/filter/servicetopology/filter.go

Line 85 in 2fad346

stf.serviceSynced = factory.Core().V1().Services().Informer().HasSynced

please add SetTransform for serviceInformer in Yurthub.

[vie-serendipity]

/PTAL @rambohe-ch

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[rambohe-ch]

/LGTM