muster release v0.23.3

Fixed

• (deps) Update module github.com/creativeprojects/go-selfupdate to v1.6.0 in #962 by @renovate[bot]
• (deps) Update module github.com/mark3labs/mcp-go to v0.56.0 in #964 by @renovate[bot]

Full Changelog: https://github.com/giantswarm/muster/compare/v0.23.2...v0.23.3