Update core-js to version 3.8.3

Author: depfu[bot]

package-lock.json

@@ -42,7 +42,7 @@
     "@typescript-eslint/eslint-plugin": "^2.34.0",
     "@typescript-eslint/parser": "^2.34.0",
     "chai": "^4.1.2",
-    "core-js": "^3.8.2",
+    "core-js": "^3.8.3",
     "eslint": "^6.8.0",
     "mocha": "^7.2.0",
     "rollup": "^1.32.1",