[gimp] build: fix flatpak manifest.

[Jehan <jehanp src gnome org>]

commit 2bc1dd1f9c67a8d5c3c10e0cd3112d43ba384af5
Author: Jehan <jehan girinstud io>
Date:   Sun Sep 5 17:06:05 2021 +0200

    build: fix flatpak manifest.
    
    The option -Dcheck-update has been changed to a combo.
    See commit f0be2256d0.

 build/flatpak/org.gimp.GIMP-nightly.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/build/flatpak/org.gimp.GIMP-nightly.json b/build/flatpak/org.gimp.GIMP-nightly.json
index 2f1a89d3dc..566a417961 100644
--- a/build/flatpak/org.gimp.GIMP-nightly.json
+++ b/build/flatpak/org.gimp.GIMP-nightly.json
@@ -524,7 +524,7 @@
             "config-opts": [ "-Dgtk-doc=false",
                              "-Dicc-directory=/run/host/usr/share/color/icc/",
                              "-Dbuild-id=org.gimp.GIMP.flatpak.nightly",
-                             "-Dcheck-update=false" ],
+                             "-Dcheck-update=no" ],
             "cleanup": [ "/bin/gimptool-2.99", "/bin/gimp-console-2.99" ],
             "buildsystem": "meson",
             "sources": [