Remove obsolete gnome-search-tool script

The main purpose of the gnome-search-tool script was to prevent
Orca and the desktop from completely locking up due to event floods.
It did not make things usable, and the need to unregister from much-
needed accessibility events made other apps less accessible. In
addition, gnome-search-tool no longer exists in GNOME. It persists
in MATE as mate-search-tool, but the problems from the GNOME 2 days
still exist and can be reproduced with other accessibility clients
without Orca running. Those problems should be addressed either in
mate-search-tool, and/or Gtk, and/or Atspi.

mate-desktop/mate-utils#352
https://gitlab.gnome.org/GNOME/at-spi2-core/-/issues/133

configure.ac

@@ -96,7 +96,6 @@ src/orca/scripts/apps/gajim/Makefile
 src/orca/scripts/apps/gcalctool/Makefile
 src/orca/scripts/apps/gedit/Makefile
 src/orca/scripts/apps/gnome-documents/Makefile
-src/orca/scripts/apps/gnome-search-tool/Makefile
 src/orca/scripts/apps/gnome-shell/Makefile
 src/orca/scripts/apps/kwin/Makefile
 src/orca/scripts/apps/notification-daemon/Makefile

src/orca/scripts/apps/Makefile.am

@@ -9,7 +9,6 @@ SUBDIRS = \
 	gedit \
 	gnome-documents \
 	gnome-shell \
-	gnome-search-tool \
 	kwin \
 	notification-daemon \
 	notify-osd \

src/orca/scripts/apps/__init__.py

@@ -7,7 +7,6 @@
            'gcalctool',
            'gedit',
            'gnome-documents',
-           'gnome-search-tool',
            'gnome-shell',
            'kwin',
            'notification-daemon',