Fix: verify worker exit when signal_exit is_cancelled

[chenyukang]

What problem does this PR solve?

When there are a lot of transaction pending in verify queue, ctrl-c may need to wait worker finishing all of them, because of this loop in verify worker, there is no chance to update self.status since worker is executing process_inner.

What is changed and how it works?

Worker should return from iteration when exit signal is sent.

Related changes

• PR to update owner/repo:
• Need to cherry-pick to the release branch

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code ci-runs-only: [ quick_checks,linters ]

Release note

Title Only: Include only the PR title in the release note.