fix(deps): bump supported Go versions to 1.27.0 and 1.26.7

[github-actions]

It's time to update Relay's supported Go versions, due to a recent upstream Go release.

The Go major release cadence is ~every 6 months; the two most recent major versions are supported.
Note that between major releases, the Go team often ships multiple minor versions.

	Current repo configuration	Desired repo configuration
Latest	1.26.6	1.27.0
Penultimate	1.25.13	1.26.7

This PR's change was generated by running:

./scripts/update-go-release-version.sh 1.27.0 1.26.7

• I have triggered CI on this PR (either close & reopen this PR in Github UI, or git commit -m "run ci" --allow-empty && git push)

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Cursor Bugbot has reviewed your changes using default effort and found 1 potential issue.

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Linter lacks Go 1.27 support

Medium Severity

CI now runs make lint on Go 1.27.0, but GOLANGCI_LINT_VERSION stays at v2.11.1, which only supports through Go 1.26. golangci-lint added 1.27 support in v2.13.0, so the lint job on latest Go is likely to fail or mis-analyze.

 

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