Manual: Update help.txt [skip CI]
Manual: Update help.txt [skip CI]

`--reuse-hazard` is a new option in the help text

Former-commit-id: 6e001650397e68fb64710a062da0d89b60388aa8 [formerly f03745f1144ee19b41081e30df01dde98b97cfe0]
Former-commit-id: ef3ebde6e52476986c9e9d0131e3e4d800ab64ce
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine