Fix a typo in development.md [skip ci]
Fix a typo in development.md [skip ci]

Former-commit-id: e2fa8e3c0bd716a79bb4ec2f614e313fe38f15af [formerly 6a899ecff65695f4c92d1ca094e07a4cd539e316]
Former-commit-id: be9fce83655a634cc5d3a08518a6a3c644f9252e
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine