[camera] Added information of video not working correctly on Android emulators…

[anniek-valk]

… to README.md.

Description

To make sure no developers try to find out why the a video with audio on an Android emulator isn't working properly, I added it to the README.md.

Related Issues

Issue 42309

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Breaking Change

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[mvanbeusekom]

Fix the title of the PR so it fits on the same line and one small typo.