WIP: Update to GNOME 41 runtime & gbrainy 2.4.4

This fails to build as follows:

    Making all in tools
    make[2]: Entering directory '/run/build/gbrainy/tools'
    /usr/lib/sdk/mono6/bin/mcs -target:winexe -out:GameXmlToGetString.exe  ./GameXmlToGetString.cs -r:../src/gbrainy.Core.dll -r:Mono.Posix
    export MONO_PATH=../src && /usr/lib/sdk/mono6/bin/mono GameXmlToGetString.exe .
    
    Unhandled Exception:
    System.TypeLoadException: Could not set up parent class, due to: Could not load type of field 'gbrainy.Core.Main.Game:default_color' (0) due to: Could not load file or assembly 'cairo-sharp, Version=1.10.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756' or one of its dependencies. assembly:/run/build/gbrainy/src/gbrainy.Core.dll type:Game member:(null)
      at GameXmlToGetString.Main (System.String[] args) [0x00061] in <2326c82eb00343b4a364a997caa15399>:0 
    [ERROR] FATAL UNHANDLED EXCEPTION: System.TypeLoadException: Could not set up parent class, due to: Could not load type of field 'gbrainy.Core.Main.Game:default_color' (0) due to: Could not load file or assembly 'cairo-sharp, Version=1.10.0.0, Culture=neutral, PublicKeyToken=0738eb9f132ed756' or one of its dependencies. assembly:/run/build/gbrainy/src/gbrainy.Core.dll type:Game member:(null)
      at GameXmlToGetString.Main (System.String[] args) [0x00061] in <2326c82eb00343b4a364a997caa15399>:0

org.gnome.gbrainy.json

@@ -3,14 +3,14 @@
     "sdk": "org.gnome.Sdk",
     "branch": "stable",
     "runtime": "org.gnome.Platform",
-    "runtime-version": "3.36",
+    "runtime-version": "41",
     "command": "gbrainy",
     "rename-appdata-file": "gbrainy.appdata.xml",
     "rename-desktop-file": "gbrainy.desktop",
     "rename-icon": "gbrainy",
     "copy-icon": true,
     "sdk-extensions": [
-        "org.freedesktop.Sdk.Extension.mono5"
+        "org.freedesktop.Sdk.Extension.mono6"
     ],
     "finish-args": [
         "--share=ipc",
@@ -20,10 +20,10 @@
         "--socket=x11"
     ],
     "build-options": {
-        "append-path": "/usr/lib/sdk/mono5/bin",
-        "append-ld-library-path": "/usr/lib/sdk/mono5/lib",
+        "append-path": "/usr/lib/sdk/mono6/bin",
+        "append-ld-library-path": "/usr/lib/sdk/mono6/lib",
         "env": {
-            "PKG_CONFIG_PATH": "/app/lib/pkgconfig:/app/share/pkgconfig:/usr/lib/pkgconfig:/usr/share/pkgconfig:/usr/lib/sdk/mono5/lib/pkgconfig"
+            "PKG_CONFIG_PATH": "/app/lib/pkgconfig:/app/share/pkgconfig:/usr/lib/pkgconfig:/usr/share/pkgconfig:/usr/lib/sdk/mono6/lib/pkgconfig"
         }
     },
     "cleanup": [
@@ -38,10 +38,11 @@
                 {
                     "type": "git",
                     "url": "https://github.com/mono/gtk-sharp.git",
-                    "commit": "c1b9bd4214b78dc426bc6e6a07c23a8ab4ab50ea"
+                    "commit": "dadc19cf1b90c5743f2776c675faac990e397a56"
                 }
             ]
         },
+        "shared-modules/intltool/intltool-0.51.json",
         {
             "name": "gbrainy",
             "sources": [
@@ -52,16 +53,16 @@
                         "url-template": "https://gent.softcatala.org/jmas/gbrainy/gbrainy-$version.tar.gz"
                     },
                     "type": "archive",
-                    "url": "https://gent.softcatala.org/jmas/gbrainy/gbrainy-2.4.2.tar.gz",
-                    "sha256": "47ebaa7fd58f55a9b10fbfcc25013e82428b292834b862dd3f728ef8feefebf3"
+                    "url": "https://gent.softcatala.org/jmas/gbrainy/gbrainy-2.4.4.tar.gz",
+                    "sha256": "1f67c220dd04c332260d810c25cb94384cca4547bcf933db3997ac69667457e9"
                 }
             ]
         },
         {
             "name": "mono-runtime",
             "buildsystem": "simple",
             "build-commands": [
-                "/usr/lib/sdk/mono5/install.sh"
+                "/usr/lib/sdk/mono6/install.sh"
             ],
             "build-options": {
                 "no-debuginfo": true,