cli/command/formatter: Error return value of ImageWrite is not checked (errcheck)

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
(cherry picked from commit 9275e2cb66)
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

cli/command/formatter/image_test.go

@@ -348,7 +348,8 @@ func TestImageContextWriteWithNoImage(t *testing.T) {
 	}
 
 	for _, context := range contexts {
-		ImageWrite(context.context, images)
+		err := ImageWrite(context.context, images)
+		assert.NilError(t, err)
 		assert.Check(t, is.Equal(context.expected, out.String()))
 		// Clean buffer
 		out.Reset()