Describe the bug
A TypeError is thrown when using Flags.version

    TypeError: Parsing --version 
        this.jsonEnabled is not a function
    See more help with --help

To Reproduce
Steps to reproduce the behavior:

1. Create a CLI using oclif generate version-bug --yes
2. Add a version flag to one of the commands
3. Run the command with --version

Expected behavior
The version printed to the console