build: Update MediaWiki requirement to 1.42

All extensions in the MediaWiki tarball are expected to track MediaWiki's release directly.

Change-Id: Id54d875300c477c9fa6084cfa20955e4446ac841

extension.json

@@ -18,7 +18,7 @@
 	"license-name": "GPL-2.0-or-later",
 	"type": "specialpage",
 	"requires": {
-		"MediaWiki": ">= 1.41"
+		"MediaWiki": ">= 1.42"
 	},
 	"ExtensionMessagesFiles": {
 		"InterwikiAlias": "Interwiki.alias.php"