Remove options property from OptionFlow

[epenet]

Breaking change

None - as long as it gets merged before 2024.12

Proposed change

SSIA, based on this comment from @MartinHjelmare
#129870 (comment)

It was added in #129718, instead of moving it from OptionsFlowWithConfigEntry to OptionsFlow it should be dropped altogether.

Needs:

• Remove usage of options property in OptionsFlow (part 1) #129895
• Remove usage of options property in OptionsFlow (part 2) #129897
• Use read-only options in emoncms options flow #129926
• Use read-only options in google cloud options flow #129927
• Use read-only options in lastfm options flow #129928
• Use read-only options in onkyo options flow #129929

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)
• Deprecation (breaking change to happen in the future)
• 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: New helpers for options flows developers.home-assistant#2435

Checklist

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