Add helper function to update and reload config entry to config flow

[jpbede]

Proposed change

We currently use something like the following in a lot of our config flows:

self.hass.config_entries.async_update_entry(
    self.existing_entry,
    data={
        CONF_EMAIL: user_input[CONF_EMAIL],
        CONF_PASSWORD: user_input[CONF_PASSWORD],
    },
)
await self.hass.config_entries.async_reload(
    self.existing_entry.entry_id
)
return self.async_abort(reason="reauth_successful")

So I thought it would be nice to have an helper function for this.

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:

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
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format 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.
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[bdraco]

Tests are failing, please check. Thanks

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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not a block

[jpbede]

Thanks