Reverted highcharts upgrade

Author: Artimatic

package-lock.json

@@ -53,7 +53,7 @@
     "feedparser": "^2.2.7",
     "file-saver": "^1.3.3",
     "hammerjs": "^2.0.8",
-    "highcharts": "^9.0.0",
+    "highcharts": "6.2.0",
     "jquery": "^3.5.0",
     "json2csv": "^3.11.5",
     "lodash": "^4.17.19",