Link to #215 instead of !216 from banner (the issue gives more information)

frontend/banners.json

@@ -32,7 +32,7 @@
 	},
 	{
 		"id": "new-ranking",
-		"text": "Cloogle uses a <a href='https://gitlab.science.ru.nl/cloogle/cloogle-org/merge_requests/216' target='_blank'>new ranking function</a> which needs to learn from its mistakes. Please <a href='https://gitlab.science.ru.nl/cloogle/cloogle-org/issues/new' target='_blank'>report</a> any issues you see.",
+		"text": "Cloogle uses a <a href='https://gitlab.science.ru.nl/cloogle/cloogle-org/issues/215' target='_blank'>new ranking function</a> which needs to learn from its mistakes. Please <a href='https://gitlab.science.ru.nl/cloogle/cloogle-org/issues/new' target='_blank'>report</a> any issues you see.",
 		"from": "Thu, 15 Nov 2018 00:00:00 UTC",
 		"until": "Thu, 29 Nov 2018 00:00:00 UTC"
 	}