Update dependency typescript to v3.8.3

Author: renovate-bot

package-lock.json

@@ -61,7 +61,7 @@
     "tslint-config-prettier": "1.18.0",
     "tslint-eslint-rules": "5.4.0",
     "tslint-plugin-prettier": "2.1.0",
-    "typescript": "3.5.1"
+    "typescript": "3.8.3"
   },
   "dependencies": {
     "pdfobject": "^2.1.1"