[meld/flatpak-ci] Fix meson script's Python version check

[Kai Willadsen <kaiw src gnome org>]

commit 32aa8c0b976f7885bc1c9b06fdbdccec0be33d35
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sat Dec 21 06:57:58 2019 +1000

    Fix meson script's Python version check

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index ff9abbcd..378c9ea9 100644
--- a/meson.build
+++ b/meson.build
@@ -15,7 +15,7 @@ endif
 
 # These requirements are kept in both `bin/meld` and `meson.build`. If you
 # update one, update the other.
-python3.language_version.version_compare('>= 3.6')
+dependency('python3', version : '>= 3.6')
 dependency('gtk+-3.0', version: '>= 3.20')
 dependency('glib-2.0', version: '>= 2.48')
 dependency('gtksourceview-4', version: '>= 4.0.0')