Update golang Docker tag to v1.26

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
golang	stage	minor	1.25-alpine → 1.26-alpine

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.43%. Comparing base (481c36e) to head (a8d5f63).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #539   +/-   ##
=======================================
  Coverage   73.43%   73.43%           
=======================================
  Files          19       19           
  Lines        2906     2906           
=======================================
  Hits         2134     2134           
  Misses        523      523           
  Partials      249      249           

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