build(deps): update go toolchain directive to v1.26.3

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
go (source)	toolchain	patch	1.26.2 → 1.26.3

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Release Notes

golang/go (go)

v1.26.3

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Configuration

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 73.48%. Comparing base (102be7d) to head (253f1d8).

Additional details and impacted files

@@           Coverage Diff           @@
##           master     #296   +/-   ##
=======================================
  Coverage   73.48%   73.48%           
=======================================
  Files          49       49           
  Lines        2248     2248           
=======================================
  Hits         1652     1652           
  Misses        411      411           
  Partials      185      185           

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