[gimp] plug-ins: spyrogimp - fix type of new layer to include alpha channel

[Jehan <jehanp src gnome org>]

commit 7d1e108b90ccfff075d68ea04447a4b5042eab81
Author: Elad Shahar <dawn ever gmail com>
Date:   Tue Sep 1 01:31:55 2020 +0300

    plug-ins: spyrogimp - fix type of new layer to include alpha channel

 plug-ins/python/spyro-plus.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/plug-ins/python/spyro-plus.py b/plug-ins/python/spyro-plus.py
index a316cf6bd2..0f26e1232e 100755
--- a/plug-ins/python/spyro-plus.py
+++ b/plug-ins/python/spyro-plus.py
@@ -1812,7 +1812,7 @@ class SpyroWindow():
 
         # Make a new GIMP layer to draw on
         self.spyro_layer = Gimp.Layer.new(img, layer_name, img.width(), img.height(),
-                                          layer.type(), 100, Gimp.LayerMode.NORMAL)
+                                          layer.type_with_alpha(), 100, Gimp.LayerMode.NORMAL)
         img.insert_layer(self.spyro_layer, None, 0)
         self.drawing_layer = self.spyro_layer