Fix cleanup of orphan device entries in AVM Fritz!Tools

[mib1185]

Proposed change

Device entry connections of type mac (CONNECTION_NETWORK_MAC) are normalized by the device entry registry which includes to lowercase them. The mac addresses returned by the fritzbox api are uppercase. So we need to ensure to search for normalized macs in device connections.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes AVM FRITZ!Box Tools does not delete the devices deleted from fritz interface #106642
• This PR is related to issue:
• Link to documentation pull request:

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[home-assistant]

Hey there @mammuth, @AaronDavidSchneider, @chemelli74, mind taking a look at this pull request as it has been labeled with an integration (fritz) you are listed as a code owner for? Thanks!

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