Fixed lint issues and missing documentation

internal/cli/fetch/command.go

@@ -7,6 +7,7 @@ import (
 	"github.com/spf13/cobra"
 )
 
+// NewCommand returns the "fetch" command, which fetches opportunities once or as a service.
 func NewCommand(opts *cli.Options) *cobra.Command {
 	cmd := &cobra.Command{
 		Use:   "fetch",