Replace "Add" with "Create" in description of Helper

[NoRi2909]

The user can create Mold indicator helpers for different purposes:

Following the HA Design guidelines this means that the description in the dialog above should use "Create" not "Add".

Note that the subline even got this correct, so we're adding some consistency within the dialog, too.

Proposed change

Replace "Add …" with "Create …" in the description key of this dialog.

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:

Checklist

• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.

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