IOS Home bar covers bottom toolbar

# Bug Report

## Problem

### What is expected to happen?

On IOS devices that use a home bar for swiping navigation, there should be space reserved for the home bar when a toolbar is present so nothing is behind it.

### What does actually happen?

The inappbrowser does not reserve any space for the home bar and places content behind it.

## Information

| How it looks (Cordova IAB) | How it should look (Safari)|
|---|---|
|  |  |

At the bottom there should be space reserved for the home bar, as demonstrated in the safari app. Using the inappbrowser plugin this is not the case.

### Command or Code

`this.inAppBrowserRef = cordova.InAppBrowser.open(url, '_blank', '');`

Source for a demo app showing this bug can be checked out from this [GitLab Repo](https://gitlab.com/basalte-public/cordova-test-inappbrowser)

### Environment, Platform, Device

IOS devices that use swipe navigation with a home bar.

### Version information

```

Cordova:

Cordova CLI : 10.0.0
Cordova Platforms : ios 6.1.1`
Cordova Plugins : cordova-plugin-inappbrowser 4.0.0

Tools:

Xcode: 11.7

```

## Checklist

- [x] I searched for existing GitHub issues
- [x] I updated all Cordova tooling to most recent version
- [x] I included all the necessary information above

Reproduce the issue with cordova.InAppBrowser.open(url, '_blank', '') using the linked GitLab demo app on an iOS device with swipe navigation and compare it with Safari. Trace the InAppBrowser iOS toolbar entry point and verify that the finished behavior reserves bottom space for the home bar so content is no longer obscured.

Written by the indexing model from the issue text.