[Cashtab] Remove unused imports from Send.js

Summary: Removed unused imports from Send.js. Related to task T2071

Test Plan:
Navigate to Send.js
Ensure the following imports are removed:
Components:
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WalletLabel
Wallet

From antd:
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Reviewers: bytesofman, #bitcoin_abc

Reviewed By: bytesofman, #bitcoin_abc

Subscribers: emack

Differential Revision: https://reviews.bitcoinabc.org/D10648