Merge pull request #325 from nextcloud/update-stable31-target-versions

chore(CI): Adjust testing matrix for Nextcloud 31 on stable31

Author: AndyScherzinger

composer.json

@@ -28,7 +28,7 @@
 		"test:unit": "vendor/bin/phpunit -c tests/phpunit.xml"
 	},
 	"require-dev": {
-		"nextcloud/ocp": "dev-master",
+		"nextcloud/ocp": "dev-stable31",
 		"bamarni/composer-bin-plugin": "^1.8"
 	},
 	"autoload-dev": {