Remove libgee and libunwind from flatpak manifest

Not needed now they are in the platform.

org.gnome.Geary.json

@@ -62,19 +62,6 @@
                 "/share/vala", "/share/girepository-1", "/share/gir-1.0",
                 "*.la", "*.a"],
     "modules": [
-        {
-            "name": "libgee",
-            "config-opts" : [
-                "--enable-introspection=no"
-            ],
-            "sources": [
-                {
-                    "type": "git",
-                    "url": "https://gitlab.gnome.org/GNOME/libgee.git",
-                    "branch": "master"
-                }
-            ]
-        },
         {
             "name": "gnome-online-accounts",
             "config-opts": [
@@ -226,16 +213,6 @@
                 }
             ]
         },
-        {
-            "name": "libunwind",
-            "sources": [
-                {
-                    "type": "git",
-                    "url": "https://git.savannah.gnu.org/git/libunwind.git",
-                    "branch": "master"
-                }
-            ]
-        },
         {
             "name": "libytnef",
             "sources": [