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

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• Has Docs included if any changes are user facing
• Has Tests included if any functionality added or changed
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  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

[waveywaves]

/lgtm

[tekton-robot]

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