Add protection to cancelled by for OMIS orders
Add protection to cancelled by for OMIS orders

This adds a small if block around the cancelled by text to ensure it
has some value before displaying this text.

This is to cover legacy orders and cases where there is no name so
the sentence will end with _by_.

uktrade/data-hub-fe-beta2,uktrade/data-hub-fe-beta2,uktrade/data-hub-frontend,uktrade/data-hub-frontend,uktrade/data-hub-frontend