composer: used Tester 2

Author: dg

composer.json

@@ -25,7 +25,7 @@
 		"latte/latte": "Allows using Latte in templates"
 	},
 	"require-dev": {
-		"nette/tester": "~1.7",
+		"nette/tester": "~2.0",
 		"nette/di": "~2.3",
 		"nette/forms": "~2.2",
 		"nette/robot-loader": "~2.2",