Remove unused constant

[raman325]

Proposed change

Migration logic was removed but we missed this constant

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• 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)
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• This PR fixes or closes issue: fixes #
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