text: Title: Add examples for BackupService and RestoreService
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  __Proposal:__
  Add examples demonstrating how to use the `BackupService` and `RestoreService` as they are both currently undocumented.
  
  __Current behavior:__
  Examples are missing apart from brief comments in the source code.
  
  __Desired behavior:__
  It would be nice to have examples demonstrating how to use both services, possibly in the `examples` directory or in the README. Personally, I would like to use `BackupService` and `RestoreService` to perform migrations but am unsure how to use these services.
  
  __Alternatives considered:__
  Other alternatives to the BackupService and RestoreService is using the Influx CLI with Python subprocess calls, but this is less testable and not preferred.
  
  __Use case:__
  Performing backups or restores using the InfluxDB Python client would be much easier with documentation.
  