Update go toolchain directive to v1.26.3

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
go (source)	toolchain	minor	1.25.3 → 1.26.3

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Release Notes

golang/go (go)

v1.26.3

v1.26.2

v1.26.1

v1.26.0

v1.25.10

v1.25.9

v1.25.8

v1.25.7

v1.25.6

v1.25.5

v1.25.4

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Configuration

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[renovate]

⚠️ Artifact update problem

Renovate failed to update an artifact related to this branch. You probably do not want to merge this PR as-is.

♻ Renovate will retry this branch, including artifacts, only when one of the following happens:

• any of the package files in this branch needs updating, or
• the branch becomes conflicted, or
• you click the rebase/retry checkbox if found above, or
• you rename this PR's title to start with "rebase!" to trigger it manually

The artifact failure details are included below:

File name: go.sum

Command failed: install-tool golang 1.24.0