Update phpspec/prophecy requirement from ^1.19 to ^1.20

Updates the requirements on [phpspec/prophecy](https://github.com/phpspec/prophecy) to permit the latest version.
- [Release notes](https://github.com/phpspec/prophecy/releases)
- [Changelog](https://github.com/phpspec/prophecy/blob/master/CHANGES.md)
- [Commits](phpspec/prophecy@v1.19.0...v1.20.0)

---
updated-dependencies:
- dependency-name: phpspec/prophecy
  dependency-type: direct:development
...

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

composer.json

@@ -62,7 +62,7 @@
         "laminas/laminas-diactoros": "^2.17 || ^3",
         "nyholm/psr7": "^1.8",
         "nyholm/psr7-server": "^1.1",
-        "phpspec/prophecy": "^1.19",
+        "phpspec/prophecy": "^1.20",
         "phpspec/prophecy-phpunit": "^2.1",
         "phpstan/phpstan": "^1.12",
         "phpunit/phpunit": "^9.6",