fn migrate

$ fn migrate

DEVELOPMENT COMMANDS
  fn migrate -   Migrate a local func.yaml file to the latest version
                 
USAGE
  fn [global options] migrate 
    
DESCRIPTION
  This command will detect the version of a func.yaml file and update it to match the latest version supported by the Fn CLI.
  Any old or unsupported attributes will be removed, and any new ones may be added.
  The current func.yaml will be renamed to func.yaml.bak and a new func.yaml created.

Some link