Bump the development-dependencies group with 2 updates (#35)

Bumps the development-dependencies group with 2 updates: [phpstan/phpstan](https://github.com/phpstan/phpstan) and [phpstan/phpstan-strict-rules](https://github.com/phpstan/phpstan-strict-rules).


Updates `phpstan/phpstan` from 2.1.17 to 2.1.21
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Changelog](https://github.com/phpstan/phpstan/blob/2.1.x/CHANGELOG.md)
- [Commits](phpstan/phpstan@2.1.17...2.1.21)

Updates `phpstan/phpstan-strict-rules` from 2.0.4 to 2.0.6
- [Release notes](https://github.com/phpstan/phpstan-strict-rules/releases)
- [Commits](phpstan/phpstan-strict-rules@2.0.4...2.0.6)

---
updated-dependencies:
- dependency-name: phpstan/phpstan
  dependency-version: 2.1.21
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: development-dependencies
- dependency-name: phpstan/phpstan-strict-rules
  dependency-version: 2.0.6
  dependency-type: direct:development
  update-type: version-update:semver-patch
  dependency-group: development-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]