Fix division by zero error in ecosystem check

[zanieb]

e.g. https://github.com/astral-sh/ruff/actions/runs/9144809516/job/25143076896?pr=11468

[codspeed-hq]

CodSpeed Performance Report

Merging #11469 will not alter performance

_{Comparing zb/eco-fix (4f29594) with main (d9ec3d5)}

Summary

✅ 30 untouched benchmarks

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

ℹ️ ecosystem check detected linter changes. (+1 -0 violations, +0 -0 fixes in 1 projects; 49 projects unchanged)

python-poetry/poetry (+1 -0 violations, +0 -0 fixes)

ruff check --no-cache --exit-zero --ignore RUF9 --output-format concise --preview

+ tests/repositories/test_legacy_repository.py:386:39: E999 SyntaxError: Got unexpected string

Changes by rule (1 rules affected)

code	total	+ violation	- violation	+ fix	- fix
E999	1	1	0	0	0

Formatter (stable)

✅ ecosystem check detected no format changes.

Formatter (preview)

✅ ecosystem check detected no format changes.

[zanieb]

Looks like this is actually a bug in reporting clone failures per e6ba39e fixing.

Regardless this seems like an improvement for now?