[gnome-online-accounts] build: Bump minimum Meson version to 0.50.0

[Debarshi Ray <debarshir src gnome org>]

commit 1abefb9d663c3b6ec13f176a8190eb6577db096d
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Oct 15 15:51:14 2019 +0200

    build: Bump minimum Meson version to 0.50.0
    
    Silences the following WARNING:
      Project targetting '>= 0.47.2' but tried to use feature introduced
        in '0.50.0': install arg in configure_file
    
    Fallout from d46cd37f1fcd26c70fcb9cb399e2872c79b55e23

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 9e47b3dd..23976cc6 100644
--- a/meson.build
+++ b/meson.build
@@ -3,7 +3,7 @@ project(
   version: '3.35.1',
   license: 'LGPL2+',
   default_options: 'buildtype=debugoptimized',
-  meson_version: '>= 0.47.2'
+  meson_version: '>= 0.50.0'
 )
 
 goa_name = 'goa'