Issue title: Unable to run example app 
 Issue body: ## Your Environment
* Plugin version: master branch
* Platform: iOS 
* OS version: mac Catalina
* Device manufacturer / model:
iPhone 7
* Flutter info (`flutter doctor`):
Doctor summary (to see all details, run flutter doctor -v):
[✓] Flutter (Channel stable, v1.17.4, on Mac OS X 10.15.3 19D76, locale en-US)
 
[✓] Android toolchain - develop for Android devices (Android SDK version 28.0.3)
[✓] Xcode - develop for iOS and macOS (Xcode 11.5)
[✓] Android Studio (version 3.6)
[!] IntelliJ IDEA Ultimate Edition (version 2020.1.2)
    ✗ Flutter plugin not installed; this adds Flutter specific functionality.
    ✗ Dart plugin not installed; this adds Dart specific functionality.
[✓] VS Code (version 1.38.1)
[✓] Connected device (1 available)

! Doctor found issues in 1 category.

I have both flutter and Dart pluggings installed

* Plugin config:
```dart <-- Syntax highlighting: DO NOT REMOVE -->

```

## Expected Behavior
Zoom meeting 

## Actual Behavior
Getting a blank page

## Steps to Reproduce
1. Zoom market place created jwt app
2. updated app key and app secret user id in meeting_screen.dart
3. start the app
4. Sart a meeting on my desktop
5. Add meeting id and meeting password in flutter app join meeting page
6. Loading meeting come with blank screen 

## Context
Trying to run example app 

## Debug logs
<!-- include iOS / Android logs
- ios XCode logs,
- use #getLog #emailLog methods (@see docs)
- Android: $ adb logcat -s TSLocationManager
-->
<details>
	<summary>Logs</summary>

``` <!-- syntax-highligting:  DO NOT REMOVE -->
2020-08-14 21:38:29.888.828.2469 Runner[1800:551434] Metal API Validation Enabled
2020-08-14 21:38:30.138918-0400 Runner[1800:551626] flutter: Observatory listening on http://116.69.203.115:49341/YGbg9af2QtY=/
2020-08-14 21:38:56.768275-0400 Runner[1800:551691] [general] Connection to daemon was invalidated
2020-08-14 21:39:33.888.828.2469 Runner[1800:551434] [Snapshotting] Snapshotting a view (0x104ad3870, _UIReplicantView) that has not been rendered at least once requires afterScreenUpdates:YES.
2020-08-14 21:39:48.233843-0400 Runner[1800:551434] [Snapshotting] Snapshotting a view (0x104af8580, _UIReplicantView) that has not been rendered at least once requires afterScreenUpdates:YES.
2020-08-14 21:39:54.852438-0400 Runner[1800:551618] flutter: Created the view
2020-08-14 21:39:55.110450-0400 Runner[1800:551434] old data has cpoied done
2020-08-14 21:39:55.112792-0400 Runner[1800:551434] [logging-persist] cannot open file at line 43353 of [378230ae7f]
2020-08-14 21:39:55.112881-0400 Runner[1800:551434] [logging-persist] os_unix.c:43353: (0) open(/var/mobile/Containers/Data/Application/B1462BC3-656F-42AF-933B-06AB307DC808/Documents/data/zoomus.tmp.db) - Undefined error: 0
2020-08-14 21:39:55.117567-0400 Runner[1800:551434] [logging] table zoom_meet_participants already exists in "create table zoom_meet_participants (itemID integer64, name text, avatar text,snsID text, snsType integer, deviceID text,roleType integer);"
2020-08-14 21:39:55.118294-0400 Runner[1800:551434] [logging] table zoom_kv already exists in "create table zoom_kv (key text, value text, section text);"
2020-08-14 21:39:55.888.828.2469 Runner[1800:551618] flutter: initialised
2020-08-14 21:39:55.888.828.2469 Runner[1800:551618] flutter: results: [1, 0]
error was 0

```

</details>

 Comments: 
 Comment 0: @romeshn Didi you get the solution for this??
I am also facing the same issue, its urgent if you can help me.

{'source': 'GithubIssues', 'repo_name_with_owner': 'decodedhealth/flutter_zoom_plugin', 'issue_id': 679480430, 'repo_stars': 131.0}