[chore] CI: test on Go 1.26

[sywhang]

No description provided.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.61%. Comparing base (16fb16b) to head (1b5c1e4).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1535      +/-   ##
==========================================
+ Coverage   98.54%   98.61%   +0.06%     
==========================================
  Files          53       53              
  Lines        3033     3033              
==========================================
+ Hits         2989     2991       +2     
+ Misses         35       34       -1     
+ Partials        9        8       -1     

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