fix: Add addon checks to fix null pointer error bug in Kubernetes versions prior to 1.25. (#7114)

[skyrise-l]

fix #7114 Add addon checks to fix null pointer error bug in Kubernetes versions prior to 1.25.
XValidation was introduced as an alpha feature in Kubernetes v1.23 and requires additional enablement. It became more stable after Kubernetes 1.25. Users encountered this error in a Kubernetes 1.23 environment.

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[codecov]

Codecov Report

Attention: Patch coverage is 42.85714% with 8 lines in your changes are missing coverage. Please review.

Project coverage is 64.89%. Comparing base (2280b96) to head (3293b50).
Report is 23 commits behind head on main.

Files	Patch %	Lines
controllers/extensions/addon_controller_stages.go	42.85%	6 Missing and 2 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7185      +/-   ##
==========================================
- Coverage   64.89%   64.89%   -0.01%     
==========================================
  Files         337      337              
  Lines       41759    41773      +14     
==========================================
+ Hits        27098    27107       +9     
- Misses      12305    12313       +8     
+ Partials     2356     2353       -3     

Flag	Coverage Δ
unittests	64.89% <42.85%> (-0.01%)	⬇️

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[ldming]

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[wangyelei]

/approved