google.maps.MouseEvent returns "r"

[Geneonosis]

Issue description
google.maps.MouseEvent does not return appropriate object, instead returns "r"

Steps to reproduce and a minimal demo of the problem

1. create a new angular project

2. npm install @agm/core (installs 3.0.0-beta.0)

3. create a component that uses
   <agm-map [latitude]="latitude" [longitude]="longitude" [zoom]="zoom"(mapRightClick)="onMapRightClick($event)"></agm-map>

4. create a function mapped to the mapRightClick output

public onMapRightClick(event: google.maps.MouseEvent): void {
   console.log("event: ", event); // <-- returns "r" ??

   const lat = event.latLng.lat(); // latLng results in undefined (should be defined)
}

_Use stackblitz.com or similar -- try this template as a starting point: https://stackblitz.com/edit/angular-google-maps-demo
^ this stackblitz.com template uses an OLD VERSION OF THE AGM/CORE DEPENDENCIES "@agm/core": "1.0.0", and is not useful for troubleshooting.

What steps should we try in your demo to see the problem?

Current behavior
google.maps.MouseEvent returns "r" resulting in event.latLng to be undefined

Expected/desired behavior
google.maps.MouseEvent should return appropriate event information so that I may collect latLng data , latLng should not be undefined.

angular-google-maps, Angular, & any other relevant dependency versions

   "dependencies": {
      "@agm/core": "^3.0.0-beta.0",
      "@angular/animations": "^10.0.0",
      "@angular/cdk": "^9.2.4",
      "@angular/common": "^10.0.0",
      "@angular/compiler": "^10.0.0",
      "@angular/core": "^10.0.0",
      "@angular/forms": "^10.0.0",
      "@angular/localize": "^10.0.0",
      "@angular/platform-browser": "^10.0.0",
      "@angular/platform-browser-dynamic": "^10.0.0",
      "@angular/router": "^10.0.0",
      "@ng-bootstrap/ng-bootstrap": "^7.0.0",
      "@types/googlemaps": "3.39.12",
      "bootstrap": "^4.5.3",
      "ngx-quill": "^12.0.0",
      "quill": "^1.3.7",
      "rxjs": "^6.5.5",
      "tslib": "^1.14.1",
      "zone.js": "^0.10.3"
   },
   "devDependencies": {
      "@angular-devkit/build-angular": "^0.1002.0",
      "@angular/cli": "^10.0.0",
      "@angular/compiler-cli": "^10.0.0",
      "@angular/language-service": "^9.0.7",
      "@types/jasmine": "^3.5.14",
      "@types/jasminewd2": "~2.0.3",
      "@types/node": "^12.19.3",
      "codelyzer": "^6.0.2",
      "jasmine-core": "^3.5.0",
      "jasmine-spec-reporter": "~4.2.1",
      "karma": "5.2.3",
      "karma-chrome-launcher": "~3.1.0",
      "karma-coverage-istanbul-reporter": "~2.1.0",
      "karma-jasmine": "~2.0.1",
      "karma-jasmine-html-reporter": "^1.5.4",
      "protractor": "7.0.0",
      "ts-node": "~8.3.0",
      "tslint": "~5.18.0",
      "typescript": "~4.0.0"
   }

Other information