update tech specs and regression k8s matrix

[vepatel]

Proposed changes

• remove versions older than 2 years from tech sepc,
• update regression job to run tests on last 5 k8s version

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 53.03%. Comparing base (a41fc13) to head (7090858).
Report is 4 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #6316      +/-   ##
==========================================
+ Coverage   52.98%   53.03%   +0.04%     
==========================================
  Files          77       77              
  Lines       15900    15921      +21     
==========================================
+ Hits         8424     8443      +19     
  Misses       7071     7071              
- Partials      405      407       +2     

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