Update timing.json Segwit Recovery functional test name

Summary: This update was overlooked when the functional test name was changed in D3194

Test Plan: Run test/functional/test_runner.py and compare the generated timing.json file

Reviewers: Fabien, #bitcoin_abc, deadalnix

Reviewed By: Fabien, #bitcoin_abc

Subscribers: markblundeberg

Differential Revision: https://reviews.bitcoinabc.org/D3258