Drop rhythmbox start/stop test, it was removed from comps

See https://pagure.io/fedora-comps/pull-request/1147 - rhythmbox
was dropped from the default Workstation package set.

Signed-off-by: Adam Williamson <awilliam@redhat.com>

needles/gnome/apps/apps_menu_rhythmbox-20210304.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "height": 25,
-      "ypos": 707,
-      "xpos": 452,
-      "width": 20,
-      "type": "match"
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "apps_menu_rhythmbox"
-  ]
-}

needles/gnome/apps/apps_run_rhythmbox-20200117.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "ypos": 82,
-      "width": 85,
-      "height": 23,
-      "type": "match",
-      "xpos": 468
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "apps_run_rhythmbox"
-  ]
-}

needles/gnome/apps/apps_run_rhythmbox-20250319.json

@@ -1,15 +0,0 @@
-{
-  "area": [
-    {
-      "type": "match",
-      "ypos": 110,
-      "xpos": 469,
-      "height": 23,
-      "width": 85
-    }
-  ],
-  "properties": [],
-  "tags": [
-    "apps_run_rhythmbox"
-  ]
-}

tests/apps_startstop/gnome/rhythmbox.pm

@@ -1,43 +0,0 @@
-use base "installedtest";
-use strict;
-use testapi;
-use utils;
-
-# This test checks that Rhythmbox starts.
-
-sub run {
-    my $self = shift;
-    my $subvariant = get_var("SUBVARIANT", "Workstation");
-
-    if ($subvariant ne "Silverblue") {
-        # Start the application
-        start_with_launcher('apps_menu_rhythmbox');
-        # To give the screen a bit of time.
-        wait_still_screen(2);
-        # On June 15th, 2022, we realized that Rhythmbox tends to
-        # crash on fresh installation when run for the first time.
-        # When this happens, softfail and try to start it again.
-        unless (check_screen("apps_run_rhythmbox")) {
-            record_soft_failure("Rhythmbox probably crashed when launched for the first time.");
-            start_with_launcher('apps_menu_rhythmbox');
-        }
-        # Check that application has started.
-        assert_screen 'apps_run_rhythmbox';
-        # Register application
-        register_application("rhythmbox");
-        # Close the application
-        quit_with_shortcut();
-    }
-    else {
-        diag("Rhythmbox not installed, skipping the test.");
-    }
-
-}
-
-sub test_flags {
-    return {};
-}
-
-1;
-
-# vim: set sw=4 et: