composer: require stable packages outside of nette

Author: dg

composer.json

@@ -36,7 +36,8 @@
 		"nette/tester": "^2.4",
 		"latte/latte": "^2.8 || ^3.0",
 		"tracy/tracy": "^2.9",
-		"phpstan/phpstan-nette": "^1.0"
+		"phpstan/phpstan-nette": "^2.0@stable",
+		"mockery/mockery": "^1.6@stable"
 	},
 	"conflict": {
 		"tracy/tracy": "<2.6"