Update dependency golangci/golangci-lint to v2.12.2

[govuk-ci]

This PR contains the following updates:

Package	Type	Update	Change
golangci/golangci-lint	uses-with	minor	v2.11 → v2.12.2

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Release Notes

golangci/golangci-lint (golangci/golangci-lint)

v2.12.2

Compare Source

Released on 2026-05-06

1. Linters bug fixes
   • gomodguard_v2: fix blocked configuration
   • gomodguard_v2: from 2.1.0 to 2.1.3
   • iface: from 1.4.1 to 1.4.2

v2.12.1

Compare Source

Released on 2026-05-01

1. Linters bug fixes
   • gomodguard_v2: fix panic with migration suggestion
2. Misc.
   • fix install.sh script (if you are still using an URL based on the branch master, please update to use https://golangci-lint.run/install.sh)

v2.12.0

Compare Source

Released on 2026-05-01

1. New linters
   • Add clickhouselint linter https://github.com/ClickHouse/clickhouse-go-linter
2. Linters new features or changes
   • dupl: from f665c8d to c99c5cf (extended detection)
   • funcorder: from 0.5.0 to 0.6.0 (new option: function)
   • goconst: add an option to ignore strings from tests
   • goconst: from 1.8.2 to 1.10.0 (extended detection)
   • gomodguard_v2: from 1.4.1 to 2.1.0 (major version with new configuration)
   • gosec: from 619ce21 to 2.26.1 (new checks: G124, G708, G709, G710)
   • govet: add inline analyzer
   • makezero: from 2.1.0 to 2.2.1 (support slice type aliases)
   • paralleltest: expose checkcleanup option
   • sloglint: from 0.11.1 to 0.12.0 (new options: allowed-keys, custom-funcs)
   • wsl_v5: from 5.6.0 to 5.8.0 (new option: cuddle-max-statements; new checks: after-decl, after-defer, after-expr, after-go, cuddle-group)
3. Linters bug fixes
   • forbidigo: from 2.3.0 to 2.3.1
   • godot: from 1.5.4 to 1.5.6
   • govet-modernize: from 0.43.0 to 0.44.0
   • ireturn: from 0.4.0 to 0.4.1
   • rowserrcheck: from 1.1.1 to c5f79b8
4. Misc.
   • Decrease cache entropy
   • Embed the JSON schema in the binary
   • Filter env vars when cloning the repository with the custom command

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• If you want to rebase/retry this PR, check this box

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This PR has been generated by Mend Renovate.

[jfharden]

I've opened an issue to do this upgrade

[jfharden]

@dependabot rebase

Edit: This is renovate, not dependabot 🫠

[github-actions]

Coverage report

Overall coverage: 87.5% 🔴 - Change vs. main: 👈 +/- 0%

Package	Statements Covered	Happy?	Change vs Main
github.com/alphagov/router	85.4%	🔴	👈 +/- 0%
github.com/alphagov/router/handlers	95.6%	⭐	👈 +/- 0%
github.com/alphagov/router/lib	82.6%	🔴	👈 +/- 0%
github.com/alphagov/router/trie	97.7%	⭐	👈 +/- 0%
github.com/alphagov/router/triemux	100.0%	⭐	👈 +/- 0%