Add flag to suppress command errors

[mattcataws]

After adding ec2-macos-utils grow root container command to ec2-macos-init in aws/ec2-macos-init@97875d5, ec2-macos-init can be seen erroring on the new module when there isn't enough free space. For this case, it would be better to not error and return exit status 0 as the default EBS volume size for EC2 mac instances is 100GB with no available space to grow.

A new flag can be introduced to the CLI to suppress any error messages that might crop up due to a lack of available free space. This will allow ec2-macos-init to not log an expected failure case and continue without errors.

Example flag: --ignore-errors

Example usage:

ec2-macos-utils grow --id root --ignore-errors

Related issue - aws/ec2-macos-init#41