Build(deps-dev): bump phpstan/phpstan in /dev-tools

Bumps [phpstan/phpstan](https://github.com/phpstan/phpstan) from 0.12.85 to 0.12.86.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Commits](phpstan/phpstan@0.12.85...0.12.86)

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

dev-tools/composer.json

@@ -7,7 +7,7 @@
         "maglnet/composer-require-checker": "^3.2.0",
         "mi-schi/phpmd-extension": "^4.3.0",
         "phpmd/phpmd": "^2.10.0",
-        "phpstan/phpstan": "^0.12.85",
+        "phpstan/phpstan": "^0.12.86",
         "phpstan/phpstan-strict-rules": "^0.12.9",
         "squizlabs/php_codesniffer": "^3.6.0",
         "vimeo/psalm": "^4.7"