- do an early check if a custom format is specified either through the
command-line, or through the cli's configuration, before adjusting
the options (to add "size" if needed).
- also removes a redundant `options.Size = opts.size` line, as this value is
already copied at the start of buildContainerListOptions()
- Update NewContainerFormat to use "table" format as a default if no format
was given.
Co-authored-by: Sebastiaan van Stijn <github@gone.nl>
Signed-off-by: Phong Tran <tran.pho@northeastern.edu>