#clean is run multiple times from the Cucumber example

[ioev]

From the readme: https://github.com/DatabaseCleaner/database_cleaner#cucumber-example

The example for adding DatabaseCleaner by hand includes a hook that is provided by DatabaseCleaner, as well as defines a second one. If cucumber-rails is included, #clean will be called 3 times (as was the case with the project I'm working on.)