Migrate Notion to new entity naming style

[bachya]

Proposed change

This PR migrates the Notion integration to the new entity naming style.

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: N/A
• This PR is related to issue: Add Entity.has_entity_name attribute  #73217
• Link to documentation pull request: N/A

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[frenck]

It seems like this integration uses title case style naming in the names of entity descriptions. The new styling also should make all of these sentence case.

[frenck]

Thanks, @bachya 👍