Remove capabilities

[colin-axner]

Summary

The module should be deleted and usage removed from ibc-go

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For Admin Use

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• Appropriate labels applied
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[damiannolan]

Capabilities usage should now be removed from each of the core msg server handlers. Other places to remove references:

• Expected interfaces Authenticate
• Usage in 04-channel and apps
• Wiring module in simapps

[colin-axner]

We should add migration docs + changelog once the removal is complete