Properly fix setting a custom coverage config file (#10692)
Properly fix setting a custom coverage config file (#10692)

Fixes the attempted fix in https://github.com/pantsbuild/pants/pull/10670.
pantsbuild/pants,jsirois/pants,pantsbuild/pants,pantsbuild/pants,pantsbuild/pants,benjyw/pants,pantsbuild/pants,benjyw/pants,benjyw/pants,pantsbuild/pants,pantsbuild/pants,benjyw/pants,jsirois/pants,jsirois/pants,benjyw/pants,benjyw/pants,benjyw/pants