Make a standalone hello world

We want to test building against the installed GTK
in ci, so lets add a standalone project.

examples/hello/meson.build

@@ -0,0 +1,10 @@
+project('hello', 'c',
+          version: '4.3.0',
+          meson_version: '>= 0.50.0',
+)
+
+executable('hello',
+  [ 'hello-world.c' ],
+  dependencies: [ dependency('gtk4') ],
+  install: false
+)

examples/meson.build

@@ -2,7 +2,6 @@ examples = [
   'builder',
   'drawing',
   'grid-packing',
-  'hello-world',
   'plugman',
   'search-bar',
   'sunny',