[eCash dev libraries] [p2 ecash-ops] Change name of folder to ecash-ops

Summary:
T2847

Depends on D12855

Change name of folder from bitcoincash-ops to ecash-ops

Test Plan: Confirm this diff only changes folder name

Reviewers: #bitcoin_abc, emack

Reviewed By: #bitcoin_abc, emack

Differential Revision: https://reviews.bitcoinabc.org/D12856