update vendor plugin requirement (#3)

Author: oscarholt

composer.json

@@ -22,7 +22,7 @@
 	"require": {
 		"silverstripe/cms": "^4 || ^5",
 		"silverstripe/framework": "^4 || ^5",
-        "silverstripe/vendor-plugin": "^1"
+        "silverstripe/vendor-plugin": "^2"
 	},
 	"minimum-stability": "dev"
 }