Don't test config on yaml import for generic camera

[davet2001]

Proposed change

The generic camera config flow includes tests for the still and stream URLs to help the user only enter valid settings. However, running these checks during yaml import has caused several problems:

• Templates not being renderable on startup YAML import can fail if there are templates in still_image_url for generic #69402
• The migration highlighting underlying errors in their yaml e.g. Generic IP camera - was working on 2022.3.8, stopped after 2022.4.0 #69461
• Authentication failures blocking yaml import rtsp authentication not working unless credentials are inline in the URL for generic #69684
  The overall main problem is that all of these leave the user with nothing imported. It looks like no import was done at all, and they have nothing to try to 'fix'.
  So my conclusion is that it is best just to assume the yaml was valid and import it, then let the user fix it later.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue: Generic Camera from m3u8 feed in 2022.03 fails to be created through UI in 2022.04.01 (Template fails in stream_source?) #69685, Generic IP camera - was working on 2022.3.8, stopped after 2022.4.0 #69461
• Link to documentation pull request:

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[balloob]

why even set a unique ID if you just use a random ID ?

[davet2001]

I thought that this was necessary, but obviously it's not!

[davet2001]

@balloob please can this go into 2022.4.2?