Bump phpstan/phpstan-symfony from 1.3.4 to 1.3.7

Bumps [phpstan/phpstan-symfony](https://github.com/phpstan/phpstan-symfony) from 1.3.4 to 1.3.7.
- [Release notes](https://github.com/phpstan/phpstan-symfony/releases)
- [Commits](phpstan/phpstan-symfony@1.3.4...1.3.7)

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

Signed-off-by: dependabot[bot] <support@github.com>