[Chat] Fixed Image Placeholder Being Shown When Fetching Failed

[jpeng-ms]

What

when internet is down or backend failed to return us an image, the image placeholder being shown to Contoso instead of the broken image icon.

This PR addresses this issue so that if image fetching is failed, we can show broken image to Contoso.

Testing for image preview

video1.mov

Testing for image gallery

video2.mov

Why

improve user experience

How Tested

1. use storybook link in this PR
2. join a teams meeting
3. send an image
4. in devtool or network conditioner, block image endpoint
5. observe that broken image is being shown
6. disable block
7. observer that placeholder being shown during fetching

Process & policy checklist

• I have updated the project documentation to reflect my changes if necessary.
• I have read the CONTRIBUTING documentation.

Is this a breaking change?

• This change causes current functionality to break.

[github-actions]

CallWithChat bundle size is increased❗.

• Current size: 5701892
• Base size: 5701521
• Diff size: 371

[github-actions]

Chat bundle size is increased❗.

• Current size: 1457649
• Base size: 1457278
• Diff size: 371

[github-actions]

Calling bundle size is not changed.

• Current size: 4970666
• Base size: 4970666
• Diff size: 0

[github-actions]

@azure/communication-react jest test coverage for stable.

	Lines	Statements	Functions	Branches
Base	46876 / 75792 61.84%	46876 / 75792 61.84%	956 / 2126 44.96%	2700 / 4434 60.89%
Current	46876 / 75814 61.83%	46876 / 75814 61.83%	957 / 2127 44.99%	2694 / 4431 60.79%
Diff	0 / 22 -0.01%	0 / 22 -0.01%	1 / 1 0.03%	-6 / -3 -0.1%

[github-actions]

@azure/communication-react jest test coverage for beta.

	Lines	Statements	Functions	Branches
Base	46871 / 75792 61.84%	46871 / 75792 61.84%	956 / 2126 44.96%	2694 / 4431 60.79%
Current	46870 / 75814 61.82%	46870 / 75814 61.82%	957 / 2127 44.99%	2683 / 4423 60.66%
Diff	-1 / 22 -0.02%	-1 / 22 -0.02%	1 / 1 0.03%	-11 / -8 -0.13%