Fix fitbit current URL not available while configuring

[colinfrei]

Proposed change

Switch to using prefer_external over require_current_request, since the config setup doesn't seem to have the request context yet.

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
sensor:
  - platform: fitbit
    clock_format: 12H
    unit_system: 'en_US'
    monitored_resources:
      - 'body/weight'
      - 'devices/battery'
      - 'activities/steps'
      - 'sleep/minutesAsleep'

Additional information

• This PR fixes or closes issue: fixes Fitbit component not starting #40517
• 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.
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• 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

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  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.
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[frenck]

Meh, this makes sense. This integration really needs to get rid of the old configurator.

Let's make sure we raise an issue for that 👍

[frenck]

Little mind change