Bump figuren-theater/phpstan from 1.2.2 to 1.2.3

Bumps [figuren-theater/phpstan](https://github.com/figuren-theater/phpstan) from 1.2.2 to 1.2.3.
- [Release notes](https://github.com/figuren-theater/phpstan/releases)
- [Changelog](https://github.com/figuren-theater/phpstan/blob/main/CHANGELOG.md)
- [Commits](figuren-theater/phpstan@1.2.2...1.2.3)

---
updated-dependencies:
- dependency-name: figuren-theater/phpstan
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>