Support password less PI-Hole installations

[mib1185]

Proposed change

With this, the config flow does recognize if an API key is needed or not.

---

This is targeted against rc because of #85264 (comment)
Another PR, based on and targeted to dev will follow in a few moments (#86184)

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 PiHole API Key now mandatory but I don't have one. #86152
• This PR is related to issue:
• Link to documentation pull request: Update PI-Hole api key condition home-assistant.io#25827

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[home-assistant]

Hey there @johnluetke, @shenxn, mind taking a look at this pull request as it has been labeled with an integration (pi_hole) you are listed as a code owner for? Thanks!

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[zSprawl]

I just put the word “none” in the field for the API and it proceeded just fine.

[mib1185]

I just put the word “none” in the field for the API and it proceeded just fine.

yes it works, but it is much more user friendly, to only be asked for entering an api key when necessary

[MartinHjelmare]

I'll put this in draft until the PR targeting dev is approved as this PR will need mostly the same code.

[frenck]

Wrong button caused by the UI jumping a bit during the page load :( Sorry about that.

[frenck]

The failing pip-check is expected as this is the RC branch.