Pin vega-lite via resolutions in top-level package.json (#126)

* Pin vega-lite in tests

* Pin vega-lite at meta level

* Remove resolutions pin in tests

Author: krassowski

package.json

@@ -19,5 +19,8 @@
   "devDependencies": {
     "lerna": "^3.22.1",
     "rimraf": "^3.0.2"
+  },
+  "resolutions": {
+    "vega-lite": "~5.5.0"
   }
 }