Update dependency @actions/github to v9

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
@actions/github (source)	8.0.1 → 9.0.0

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Release Notes

actions/toolkit (@​actions/github)

v9.0.0

• Breaking change: Package is now ESM-only
  • CommonJS consumers must use dynamic import() instead of require()
  • Example: const { getOctokit, context } = await import('@​actions/github')
• Fix TypeScript compilation by migrating to ESM, enabling proper imports from @octokit/core/types

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