status/plugin: do not test connection if disabled

so that if one disables the plugin (e.g. because it is offline),
it will work even when the server is not reachable

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

PVE/Status/Plugin.pm

@@ -129,6 +129,9 @@ sub send {
 sub test_connection {
     my ($class, $cfg) = @_;
 
+    # do not check connection for disabled plugins
+    return if $cfg->{disable};
+
     my $conn = $class->_connect($cfg);
     $class->_disconnect($conn);
 }