chore: fix composer package name

Author: kenjis

composer.json.dist

@@ -5,6 +5,6 @@
 		"codeigniter/framework": "3.1.*"
 	},
 	"require-dev": {
-		"mikey179/vfsStream": "1.1.*"
+		"mikey179/vfsstream": "1.1.*"
 	}
 }