chore(deps): update go toolchain directive to v1.26.4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
go (source)	toolchain	patch	1.26.3 → 1.26.4

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Release Notes

golang/go (go)

v1.26.4

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Configuration

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.22%. Comparing base (0acb43e) to head (86d7d46).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #643   +/-   ##
=======================================
  Coverage   87.22%   87.22%           
=======================================
  Files          13       13           
  Lines        2090     2090           
=======================================
  Hits         1823     1823           
  Misses        180      180           
  Partials       87       87           

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