[release-18.0] Release of v18.0.5

[shlomi-noach]

Includes the release notes and release commit for the v18.0.5 release. Once this PR is merged, we will be able to tag v18.0.5 on the merge commit.

[vitess-bot]

Review Checklist

Hello reviewers! 👋 Please follow this checklist when reviewing this Pull Request.

General

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