Fix campaign events endpoint docstring
Fix campaign events endpoint docstring

pulilab/rapidpro,tsotetsi/textily-web,pulilab/rapidpro,pulilab/rapidpro,tsotetsi/textily-web,tsotetsi/textily-web,tsotetsi/textily-web,tsotetsi/textily-web,pulilab/rapidpro,pulilab/rapidpro