chore(deps): update golang docker tag to v1.26.4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
golang	stage	minor	1.25.7-bookworm → 1.26.4-bookworm

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 13.24%. Comparing base (cb6417a) to head (6957a0f).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #143   +/-   ##
=======================================
  Coverage   13.24%   13.24%           
=======================================
  Files          30       30           
  Lines         634      634           
=======================================
  Hits           84       84           
  Misses        546      546           
  Partials        4        4           

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