Proposed change

Sending a message to a group notify entity without the title parameter fails with a string value is None for dictionary value @ data['title'] error.

This PR fixes the issue by checking the title parameter is present and supported before passing the value to the service.

How to reproduce the bug:

1. Go to Settings > Devices & services > Helpers > Create helper
2. In the "Create helper" dialog, click on Group then Notify group
3. Enter group In the Name field, then select 1 or more notify entities in the Members field then click Submit.
4. The notify.group entity is created.
5. Run the following action:

action: notify.send_message
data:
  message: test
target:
  entity_id: notify.group

6. The following error is observed: Failed to perform the action notify.send_message. string value is None for dictionary value @ data['title']. Got None (Expected result: message is sent to all members in the group)

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:
• Link to developer documentation pull request:
• Link to frontend pull request:

Checklist

• I understand the code I am submitting and can explain how it works.
• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

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