Auto lower case username for Schlage auth flows

[frenck]

Proposed change

Apparently, the login username for Schlage is always lowercase. This has led to confusion a few times now. This PR is aimed to avoid confusion by lowering the casing of the user input during the config flows.

Ref:

• Cannot log into Schlage Integration #102282 (comment)
• https://community.home-assistant.io/t/cannot-login-into-the-schlege-core-integration/628493
• Username/Email must be in lowercase home-assistant.io#34356

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 Username/Email must be in lowercase home-assistant.io#34356
• This PR is related to issue:
• Link to documentation pull request:

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[home-assistant]

Hey there @dknowles2, mind taking a look at this pull request as it has been labeled with an integration (schlage) you are listed as a code owner for? Thanks!

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[dknowles2]

Thanks!

[frenck]

Rebased to resolve a merge conflict.