fix(supervisor): correct misleading error comment in LogIndexer

[aso20455]

The comment for FetchReceipt error variant incorrectly said "Failed to fetch logs for a block from the state manager" but the error wraps ManagedNodeError from receipt fetching operations, not log fetching from state manager. Updated to accurately describe what the error represents.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 77.1%. Comparing base (86910c9) to head (f2f0f64).
⚠️ Report is 6 commits behind head on main.
✅ All tests successful. No failed tests found.

❗ There is a different number of reports uploaded between BASE (86910c9) and HEAD (f2f0f64). Click for more details.

HEAD has 19 uploads less than BASE

Flag	BASE (86910c9)	HEAD (f2f0f64)
proof	7	0
e2e	11	0
unit	2	1

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[github-actions]

This pull request has been automatically marked as stale because it has been inactive for 3 weeks.
It will be closed in 1 week if no further activity occurs.
If you believe this PR should remain open, please add the M-prevent-stale label or leave a comment.