patch 9.0.1112: test_mswin_event() can hang

Problem:    test_mswin_event() can hang.
Solution:   Add the "execute" argument to process events right away.
            (Christopher Plewright, closes #11760)
diff --git a/src/testdir/test_gui.vim b/src/testdir/test_gui.vim
index 0c1e0a5..013b177 100644
--- a/src/testdir/test_gui.vim
+++ b/src/testdir/test_gui.vim
@@ -1694,7 +1694,7 @@
     \ [[0x11, 0x10, 0x28], "C-S-Down", 4],
     \ [[0x11, 0x30], "C-0", 4],
     \ [[0x11, 0x31], "C-1", 4],
-    \ [[0x11, 0x32], "C-2", 4],
+    \ [[0x11, 0x32], "C-@", 0],
     \ [[0x11, 0x33], "C-3", 4],
     \ [[0x11, 0x34], "C-4", 4],
     \ [[0x11, 0x35], "C-5", 4],
@@ -1715,6 +1715,7 @@
     \ [[0x11, 0x6A], "C-*", 4],
     \ [[0x11, 0x6B], "C-+", 4],
     \ [[0x11, 0x6D], "C--", 4],
+    \ [[0x11, 0xBD], "C-_", 0],
     \ [[0x11, 0x70], "C-F1", 4],
     \ [[0x11, 0x10, 0x70], "C-S-F1", 4],
     \ [[0x11, 0x71], "C-F2", 4],