Allow home assistant backups to exclude database

[mdegat01]

Proposed change

Recent releases of Home Assistant have improved the default database option to the point where its performance has surpassed that of the MariaDB add-on in most if not all cases. In addition to fixing the consistency issues created by backups.

One of the remaining reasons given by users for continuing to use the add-on over the default option is inability to exclude the often quite large database file from their backups, whereas an add-on can easily be excluded. This PR adds an option to exclude the database file when making a backup of Home Assistant. It also includes a new setting which allows the database to be excluded by default to handle times when there's no space for options (like the partial backup on update).

Limitation - it only works for the default database file. Users can move or rename this file using the database options, if they do so it will not be excluded as supervisor does not look at or understand Home Assistant config.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (which adds functionality to the supervisor)
• 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:
• Link to documentation pull request: Document API options for excluding DB from backups developers.home-assistant#1941
• Link to cli pull request: Add exclude DB options to CLI cli#427

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 supervisor tests)
• Tests have been added to verify that the new code works.

If API endpoints of add-on configuration are added/changed:

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