Fixed docstring [skip CI]
Fixed docstring [skip CI]


Former-commit-id: 94009937c690a27f2ba3d87913773b8d765f7ca6 [formerly 8bc19b89575f4c01e1f034aad237d313a4f30fb2]
Former-commit-id: ea058dc3a3d98ca54e0fc7ad41f43af15c72b32e
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine