Update phpstan/phpstan requirement from ^0.11 to ^0.12

Updates the requirements on [phpstan/phpstan](https://github.com/phpstan/phpstan) to permit the latest version.
- [Release notes](https://github.com/phpstan/phpstan/releases)
- [Commits](phpstan/phpstan@0.11...0.12.0)

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

Author: dependabot-preview[bot]

composer.json

@@ -35,7 +35,7 @@
   "require-dev": {
     "infection/infection": "^0.15",
     "orchestra/testbench": "^4.4",
-    "phpstan/phpstan": "^0.11",
+    "phpstan/phpstan": "^0.12",
     "phpunit/phpunit": "^8.4",
     "laravel/cashier": "^7.0|^8.0|^9.0|^10.0"
   },