cleanup dependencies and fix versions (#5835)

* remove core-js

* fix lib versions

* remove unused lib

* upgrade rxjs

package.json

@@ -89,11 +89,9 @@
     "@mat-datetimepicker/core": "^4.1.0",
     "@mat-datetimepicker/moment": "^4.1.0",
     "@ngx-translate/core": "^13.0.0",
-    "@types/request": "^2.48.3",
     "adf-tslint-rules": "0.0.6",
     "chart.js": "2.9.3",
     "classlist.js": "1.1.20150312",
-    "core-js": "^2.5.4",
     "custom-event-polyfill": "0.3.0",
     "minimatch": "^3.0.4",
     "minimatch-browser": "1.0.0",
@@ -104,11 +102,9 @@
     "pdfjs-dist": "2.3.200",
     "raphael": "2.2.7",
     "remark-validate-links": "^8.0.0",
-    "rxjs": "^6.5.5",
+    "rxjs": "^6.6.0",
     "snyk": "^1.316.1",
-    "systemjs": "0.19.27",
     "tslib": "^2.0.0",
-    "web-animations-js": "^2.3.2",
     "zone.js": "~0.10.2"
   },
   "devDependencies": {
@@ -125,6 +121,7 @@
     "@types/minimatch": "^3.0.3",
     "@types/node": "^12.11.1",
     "@types/pdfjs-dist": "^2.1.3",
+    "@types/request": "^2.48.5",
     "@types/selenium-webdriver": "^3.0.8",
     "ajv-cli": "^3.0.0",
     "bundlesize": "0.18.0",
@@ -165,7 +162,6 @@
     "mini-css-extract-plugin": "^0.9.0",
     "nconf": "^0.10.0",
     "ng-packagr": "^10.0.0",
-    "node-sass": "4.13.0",
     "optimize-css-assets-webpack-plugin": "^5.0.3",
     "protractor": "^5.4.2",
     "protractor-retry": "^1.2.9",