build: Bump phpstan/phpstan

Bumps the dependencies group in /vendor-bin/phpstan with 1 update: [phpstan/phpstan](https://github.com/phpstan/phpstan).


Updates `phpstan/phpstan` from 1.12.0 to 1.12.3
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/2.0.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@1.12.0...1.12.3)

---
updated-dependencies:
- dependency-name: phpstan/phpstan
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: dependencies
...

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