Use custom app to play camera stream using Google Assistant

[bramkragten]

Proposed change

Use the home assistant cast app to play camera streams from google assistant, so correctly set the format.
Needs home-assistant/frontend#7160

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

Example entry for configuration.yaml:

# Example configuration.yaml

Additional information

• This PR fixes or closes issue: fixes Playing camera stream using google assistant is broken in 0.115 #40719
• This PR is related to issue:
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• Untested files have been added to .coveragerc.

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[probot-home-assistant]

Hey there @emontnemery, mind taking a look at this pull request as its been labeled with an integration (cast) you are listed as a codeowner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[ioannispelelis]

Hello, is this expected that this function requires Nabu Casa and cannot work if we have made a manual integration with google home or should i open a bug?

[bramkragten]

Don't add comments to closed PR's and especially not the same comment both on a closed PR and on a closed issue.

[ioannispelelis]

Don't add comments to closed PR's and especially not the same comment both on a closed PR and on a closed issue.

Sorry i first saw this PR and after the issue. Shall i open a new issue or can i continue the discussion on the existing issue?