chore: bump golangci-lint to use go1.27

[giortzisg]

Description

This bumps the lint action to use go 1.27 along with the new lint rules. Also fixes the failing ones.

#skip-changelog

Issues

Changelog Entry Instructions

To add a custom changelog entry, uncomment the section above. Supports:

• Single entry: just write text
• Multiple entries: use bullet points
• Nested bullets: indent 4+ spaces

For more details: custom changelog entries

Reminders

• Add GH Issue ID & Linear ID
• PR title should use conventional commit style (feat:, fix:, ref:, meta:)
• For external contributors: CONTRIBUTING.md, Sentry SDK development docs, Discord community

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