build(deps): bump qs from 6.5.2 to 6.6.0 in /ui

Bumps [qs](https://github.com/ljharb/qs) from 6.5.2 to 6.6.0.
- [Release notes](https://github.com/ljharb/qs/releases)
- [Changelog](https://github.com/ljharb/qs/blob/master/CHANGELOG.md)
- [Commits](https://github.com/ljharb/qs/compare/v6.5.2...v6.6.0)

Signed-off-by: dependabot[bot] <support@dependabot.com>

ui/package.json

@@ -26,7 +26,7 @@
     "moment": "2.22.2",
     "object-hash": "1.3.1",
     "prop-types": "15.6.2",
-    "qs": "6.5.2",
+    "qs": "6.6.0",
     "react": "16.6.3",
     "react-autosuggest": "9.4.2",
     "react-datepicker": "2.0.0",

ui/yarn.lock

@@ -9021,6 +9021,11 @@ qs@6.5.2, qs@~6.5.2:
   resolved "https://registry.yarnpkg.com/qs/-/qs-6.5.2.tgz#cb3ae806e8740444584ef154ce8ee98d403f3e36"
   integrity sha512-N5ZAX4/LxJmF+7wN74pUD6qAh9/wnvdQcjq9TZjevvXzSUo7bfmw91saqMjzGS2xq91/odN2dW/WOl7qQHNDGA==
 
+qs@6.6.0:
+  version "6.6.0"
+  resolved "https://registry.yarnpkg.com/qs/-/qs-6.6.0.tgz#a99c0f69a8d26bf7ef012f871cdabb0aee4424c2"
+  integrity sha512-KIJqT9jQJDQx5h5uAVPimw6yVg2SekOKu959OCtktD3FjzbpvaPr8i4zzg07DOMz+igA4W/aNM7OV8H37pFYfA==
+
 querystring-es3@^0.2.0:
   version "0.2.1"
   resolved "https://registry.yarnpkg.com/querystring-es3/-/querystring-es3-0.2.1.tgz#9ec61f79049875707d69414596fd907a4d711e73"