Update dependency ava to v6

Author: renovate[bot]

package.json

@@ -37,7 +37,7 @@
     "@babel/preset-env": "7.14.2",
     "@babel/register": "7.13.16",
     "@iterable-iterator/range": "^1.0.0",
-    "ava": "3.15.0",
+    "ava": "6.1.3",
     "coveralls": "3.1.0",
     "esdoc": "1.1.0",
     "esdoc-inject-script-plugin": "1.0.0",