chore: update gh actions

[tatomyr]

What/Why/How?

Updated GH action versions.

Check yourself

• This PR follows the contributing guide
• All new/updated code is covered by tests
• Core code changed? - Tested with other Redocly products (internal contributions only)
• New package installed? - Tested in different environments (browser/node)
• Documentation update has been considered

Security

• The security impact of the change has been considered
• Code follows company security practices and guidelines

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Note

Medium Risk
Moderate risk because it updates third-party GitHub Actions used in release and CI workflows (Docker registry logins and Slack notifications), which could impact publishing/notifications if behavior changed.

Overview
Bumps pinned GitHub Action revisions across CI workflows.

Updates markdownlint-cli2-action (docs checks), docker/login-action (DockerHub/GHCR auth during releases), slackapi/slack-github-action (release notifications), and vitest-coverage-report-action (test coverage reporting) to newer versions without changing workflow logic.

^{Written by Cursor Bugbot for commit 3b2350f. This will update automatically on new commits. Configure here.}

[changeset-bot]

⚠️ No Changeset found

Latest commit: 3b2350f

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

This PR includes no changesets

When changesets are added to this PR, you'll see the packages that this PR includes changesets for and the associated semver types

Click here to learn what changesets are, and how to add one.

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[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	79.93% (🎯 79%)	6689 / 8368
🔵	Statements	79.34% (🎯 79%)	6916 / 8716
🔵	Functions	83.05% (🎯 82%)	1353 / 1629
🔵	Branches	71.64% (🎯 71%)	4555 / 6358

File Coverage

No changed files found.

Generated in workflow #9284 for commit 3b2350f by the Vitest Coverage Report Action

[github-actions]

CLI Version	Mean Time ± Std Dev (s)	Relative Performance (Lower is Faster)
cli-latest	3.504s ± 0.025s	▓ 1.01x
cli-next	3.486s ± 0.027s	▓ 1.00x (Fastest)