`pkg/api/types`: consistenly include or exclude stdout and stderr writers

[AkihiroSuda]

The current types are inconsistent; some types contain the io.Writer for stdout, some types does not.

nerdctl/pkg/api/types/apparmor_types.go

Lines 31 to 38 in 0b051a5

	type ApparmorListCommandOptions struct {
	// Only display profile names
	Quiet bool
	// Format the output using the given go template
	Format string
	// Writer is the output writer
	Writer io.Writer
	}

nerdctl/pkg/api/types/network_types.go

Lines 19 to 26 in 0b051a5

	type NetworkListCommandOptions struct {
	// GOptions is the global options
	GOptions GlobalCommandOptions
	// Quiet only show numeric IDs
	Quiet bool
	// Format the output using the given Go template, e.g, '{{json .}}', 'wide'
	Format string
	}