[gnome-continuous] Bump Meson to new stable release

[Emmanuele Bassi <ebassi src gnome org>]

commit dd96e3d2881d317b90f769c9fc4793b63624b89a
Author: Emmanuele Bassi <ebassi gnome org>
Date:   Wed Apr 17 10:33:12 2019 +0100

    Bump Meson to new stable release
    
    Hopefully, with fewer regressions this time.

 manifest.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/manifest.json b/manifest.json
index f316f3d..c975e70 100644
--- a/manifest.json
+++ b/manifest.json
@@ -67,7 +67,7 @@
 
                 {"src": "git:https://github.com/mesonbuild/meson.git";,
                  "name": "meson",
-                 "tag": "0.49.2",
+                 "tag": "0.50.1",
                  "component": "devel",
                  "patches": ["python-meson-buildsys.patch"]},