Repository: flutter
Issue: [flutter_markdown] MarkdownBody tries to render the object as an image
Labels: package,team-ecosystem,has reproducible steps,P3,found in release: 2.2,p: flutter_markdown,triaged-ecosystem

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## Steps to Reproduce

<!-- You must include full steps to reproduce so that we can reproduce the problem. -->

1. Add [flutter_markdown: ^0.6.4](https://pub.dev/packages/flutter_markdown) to your app.
2. Add this Widget:

```dart
MarkdownBody(data: '![](https://github-readme-stats.vercel.app/api/top-langs/?username=omatt&layout=compact)]'),
```

3. Run the app either on mobile or web

<details>
<summary><b>Error Logs</b></summary>

```
======== Exception caught by image resource service ================================================
The following ImageCodecException was thrown resolving an image codec:
Failed to load network image.
Image URL: https://github-readme-stats.vercel.app/api/top-langs/?username=omatt&layout=compact
Trying to load an image from another domain? Find answers at:
https://flutter.dev/docs/development/platform-integration/web-images

When the exception was thrown, this was the stack: 
Image provider: NetworkImage("https://github-readme-stats.vercel.app/api/top-langs/?username=omatt&layout=compact", scale: 1)
Image key: NetworkImage("https://github-readme-stats.vercel.app/api/top-langs/?username=omatt&layout=compact", scale: 1)
====================================================================================================
```

</details>

**Expected results:** <!-- what did you want to see? -->

It should be able to render the Widget as

![](https://github-readme-stats.vercel.app/api/top-langs/?username=omatt&layout=compact)

**Actual results:** <!-- what did you see? -->

<img width="646" alt="Screen Shot 2021-08-07 at 10 23 06 PM" src="https://user-images.githubusercontent.com/4143153/128603383-e9d414ed-f9e1-4449-8c50-f6c70a9ace1d.png">

<details>
  <summary>Logs</summary>

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```
```

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     Run `flutter analyze` and attach any output of that command below.
     If there are any analysis errors, try resolving them before filing this issue.
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```
```

<!-- Finally, paste the output of running `flutter doctor -v` here. -->

```
[✓] Flutter (Channel stable, 2.2.3, on macOS 11.5.1 20G80 darwin-x64, locale en)
    • Flutter version 2.2.3
    • Framework revision f4abaa0735 (5 weeks ago), 2021-07-01 12:46:11 -0700
    • Engine revision 241c87ad80
    • Dart version 2.13.4

[✓] Android toolchain - develop for Android devices (Android SDK version 30.0.2)
    • Android SDK
    • Platform android-30, build-tools 30.0.2
    • Java binary at: /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java
    • Java version Java(TM) SE Runtime Environment (build 1.8.0_221-b11)
    • All Android licenses accepted.

[✓] Xcode - develop for iOS and macOS
    • Xcode at /Applications/Xcode.app/Contents/Developer
    • Xcode 12.0.1, Build version 12A7300
    • CocoaPods version 1.10.0

[✓] Chrome - develop for the web
    • Chrome at /Applications/Google Chrome.app/Contents/MacOS/Google Chrome

[!] Android Studio (version 2020.3)
    • Android Studio at /Applications/Android Studio.app/Contents
    • Flutter plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/9212-flutter
    • Dart plugin can be installed from:
      🔨 https://plugins.jetbrains.com/plugin/6351-dart
    ✗ Unable to find bundled Java version.
    • Try updating or re-installing Android Studio.

[✓] VS Code (version 1.59.0)
    • VS Code at /Applications/Visual Studio Code.app/Contents
    • Flutter extension version 3.25.0

[✓] Connected device (2 available)
    • iPhone Xs (mobile) • 82CF4677-9933-4698-AD5C-823D6E93F283 • ios            • com.apple.CoreSimulator.SimRuntime.iOS-12-4 (simulator)
    • Chrome (web)       • chrome                               • web-javascript • Google Chrome 92.0.4515.131

! Doctor found issues in 1 category.

```

</details>