Update friends-of-phpspec/phpspec-code-coverage requirement

Updates the requirements on friends-of-phpspec/phpspec-code-coverage to permit the latest version.

---
updated-dependencies:
- dependency-name: friends-of-phpspec/phpspec-code-coverage
  dependency-type: direct:development
...

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

composer.json

@@ -22,7 +22,7 @@
     },
     "require-dev": {
         "ecphp/php-conventions": "^1",
-        "friends-of-phpspec/phpspec-code-coverage": "^5.0.0",
+        "friends-of-phpspec/phpspec-code-coverage": "^6.1.0",
         "infection/infection": "^0.24.0",
         "infection/phpspec-adapter": "^0.1.2",
         "phpspec/phpspec": "^7"