[gtksourceview] build: reduce GTK requirement

[Christian Hergert <chergert src gnome org>]

commit 46535be53956384d0d17c73c86195f061b7428bc
Author: Christian Hergert <chergert redhat com>
Date:   Mon Oct 11 17:55:43 2021 -0700

    build: reduce GTK requirement
    
    To help CI keep going.

 meson.build | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/meson.build b/meson.build
index 7d14bc80..9487fd15 100644
--- a/meson.build
+++ b/meson.build
@@ -68,7 +68,7 @@ build_gtk_doc = get_option('gtk_doc')
 cc = meson.get_compiler('c')
 
 glib_req_version = '2.66'
-gtk_req_version = '4.4'
+gtk_req_version = '4.2'
 
 libm_dep = cc.find_library('m', required: false)