[DEPS]: Bump boxuk/wp-muplugin-loader from 1.4.1 to 1.5.0

Bumps [boxuk/wp-muplugin-loader](https://github.com/boxuk/wp-muplugin-loader) from 1.4.1 to 1.5.0.
- [Release notes](https://github.com/boxuk/wp-muplugin-loader/releases)
- [Commits](boxuk/wp-muplugin-loader@1.4.1...1.5.0)

---
updated-dependencies:
- dependency-name: boxuk/wp-muplugin-loader
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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