[gtk/tests-cleanup] tests: Drop testexpander

[Matthias Clasen <matthiasc src gnome org>]

commit dc8c37120e9bbd151d1123671542fa6783e03c4b
Author: Matthias Clasen <mclasen redhat com>
Date:   Wed May 13 16:23:48 2020 -0400

    tests: Drop testexpander
    
    This was copied into gtk4-demo at some point.
    
    See #2738

 tests/meson.build    |  1 -
 tests/testexpander.c | 81 ----------------------------------------------------
 2 files changed, 82 deletions(-)
---
diff --git a/tests/meson.build b/tests/meson.build
index 0f90065898..218a72677f 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -83,7 +83,6 @@ gtk_tests = [
   ['testgrouping'],
   ['testtooltips'],
   ['testexpand'],
-  ['testexpander'],
   ['testvolumebutton'],
   ['testscrolledwindow'],
   ['testscrolledge'],