cli/connhelper/commandcon: use stdlib errors

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/connhelper/commandconn/commandconn.go

@@ -28,7 +28,6 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 )
 
@@ -149,7 +148,7 @@ func (c *commandConn) handleEOF(err error) error {
 			c.stderrMu.Lock()
 			stderr := c.stderr.String()
 			c.stderrMu.Unlock()
-			return errors.Errorf("command %v did not exit after %v: stderr=%q", c.cmd.Args, err, stderr)
+			return fmt.Errorf("command %v did not exit after %v: stderr=%q", c.cmd.Args, err, stderr)
 		}
 	}
 
@@ -159,7 +158,7 @@ func (c *commandConn) handleEOF(err error) error {
 	c.stderrMu.Lock()
 	stderr := c.stderr.String()
 	c.stderrMu.Unlock()
-	return errors.Errorf("command %v has exited with %v, make sure the URL is valid, and Docker 18.09 or later is installed on the remote host: stderr=%s", c.cmd.Args, werr, stderr)
+	return fmt.Errorf("command %v has exited with %v, make sure the URL is valid, and Docker 18.09 or later is installed on the remote host: stderr=%s", c.cmd.Args, werr, stderr)
 }
 
 func ignorableCloseError(err error) bool {