Remove specific Kubernetes version instructions and link to the Vites…

[anshikavashistha]

To update the examples/operator/README.md file by removing the --kubernetes-version=v1.19.5 flag and adding a reference to the compatibility matrix in the official documentation.

• Removed specific Kubernetes version instructions from examples/operator/README.md.
• Added a link to the Vitess Operator Compatibility Matrix for up-to-date Kubernetes version information.
• This change centralizes Kubernetes version recommendations and ensures users are directed to the most current documentation.
  Related Issue:#1022

[vitess-bot]

Review Checklist

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• vtctl command output order should be stable and awk-able.

[anshikavashistha]

@GuptaManan100 @frouioui PTAL

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.96%. Comparing base (0d6b768) to head (3808f0e).
Report is 20 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #16610      +/-   ##
==========================================
+ Coverage   68.83%   68.96%   +0.13%     
==========================================
  Files        1558     1562       +4     
  Lines      200042   200760     +718     
==========================================
+ Hits       137693   138458     +765     
+ Misses      62349    62302      -47     

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[mattlord]

Thanks, @anshikavashistha !