[gtk+] tests: Remove completely outdated test

[Benjamin Otte <otte src gnome org>]

commit e78402ec9437e634cdc382fb428179b293878067
Author: Benjamin Otte <otte redhat com>
Date:   Tue Oct 31 19:03:55 2017 +0100

    tests: Remove completely outdated test
    
    The test was fiddling with screens and trying crazy stuff. We don't do
    things like that anymore.

 tests/meson.build        |    1 -
 tests/testmultidisplay.c |  181 ----------------------------------------------
 2 files changed, 0 insertions(+), 182 deletions(-)
---
diff --git a/tests/meson.build b/tests/meson.build
index ba6d090..3b5bdf5 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -65,7 +65,6 @@ gtk_tests = [
   ['testlockbutton'],
   ['testmenubutton'],
   ['testmountoperation'],
-  ['testmultidisplay'],
   ['testnotebookdnd'],
   ['testnouiprint'],
   ['testorientable'],