Use consolidated constant for "description"

[spacegaier]

Breaking change

Proposed change

This PR moves the "description" conf constant to the global ones, to prevent it from having to re-defined in the integrations over and over again.

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)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

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[Quentame]

LGTM

[MartinHjelmare]

Thanks!