Update dependency ava to v3

Author: renovate-bot

package.json

@@ -17,7 +17,7 @@
   },
   "devDependencies": {
     "@types/node": "12.12.7",
-    "ava": "2.4.0",
+    "ava": "3.7.1",
     "eslint": "6.8.0",
     "eslint-config-standard": "14.1.1",
     "eslint-plugin-import": "2.20.2",