chore(deps): bump Go from 1.26.4 to 1.26.5

[infernus01]

Changes

Bump the Go toolchain version from 1.26.4 to 1.26.5 to
remediate stdlib CVEs
CVEs fixed by this change:

• CVE-2026-39822 (Important) — stdlib, fixed in Go 1.26.5
• CVE-2026-42505 (Moderate) — stdlib, fixed in Go 1.26.5

Submitter Checklist

As the author of this PR, please check off the items in this checklist:

• Has Docs included if any changes are user facing
• Has Tests included if any functionality added or changed
• Follows the commit message standard
• Meets the Tekton contributor standards (including
  functionality, content, code)
• Release notes block below has been updated with any user facing changes (API changes, bug fixes, changes requiring upgrade notices or deprecation warnings)
• Release notes contains the string "action required" if the change requires additional action from users switching to the new release

Release Notes

NONE

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 72.65%. Comparing base (93ff01b) to head (d7e7e4f).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1904      +/-   ##
==========================================
+ Coverage   72.60%   72.65%   +0.05%     
==========================================
  Files          58       58              
  Lines        3855     3855              
==========================================
+ Hits         2799     2801       +2     
+ Misses        763      761       -2     
  Partials      293      293              

Flag	Coverage Δ
unit-tests	72.65% <ø> (+0.05%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Harness.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[enarha]

/lgtm

[tekton-robot]

New changes are detected. LGTM label has been removed.

[tekton-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by:
To complete the pull request process, please ask for approval from enarha after the PR has been reviewed.

The full list of commands accepted by this bot can be found here.

Details

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment