test: Load test spec from Gerrit instead of GitHub and commit to repo

Bug: T370834
Change-Id: I59801ad4509b546bf1af1902b158830ec0f96268

Author: anny21

.gitignore

@@ -1,6 +1,6 @@
 /coverage/
 /doc/
-/test/data-*
+/test/data-fixture*
 /vendor/
 /.idea
 /.phpunit.result.cache

composer.json

@@ -40,7 +40,11 @@
 		"fix": [
 			"phpcbf"
 		],
-		"phpcs": "phpcs -sp"
+		"phpcs": "phpcs -sp",
+		"fetch-data": [
+			"rm -f test/data-v*.json",
+			"curl https://gerrit.wikimedia.org/r/plugins/gitiles/mediawiki/libs/node-cssjanus/+/refs/tags/v2.3.0/test/data.json?format=TEXT | base64 --decode > test/data-v2.3.0.json"
+		]
 	},
 	"config": {
 		"allow-plugins": {