Fix rebase issue that introduced a linter error
Fix rebase issue that introduced a linter error

Summary: There was a rebase issue before landing D9972 which duplicated an import.

Test Plan:
  arc lint

Reviewers: #bitcoin_abc, majcosta, PiRK

Reviewed By: #bitcoin_abc, majcosta, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D9997

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