Small fix to UcerfFilter [skip hazardlib]
Small fix to UcerfFilter [skip hazardlib]


Former-commit-id: 79cbd6b315c8be4c45cbf7ac29c1e57d0383239e [formerly b1282d378a703b8a9f4ae52861cb55bafb2d3b0c]
Former-commit-id: 0353487c1795e69ce1640f32eef4ec234dc271d2
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine