disable file picker filters

macOS's file picker had issues with them being enabled and it works
just fine without the filter being added. Probably applies to other
file picker interfaces too

src/components/chatinput.cpp

@@ -149,11 +149,6 @@ void ChatInputTextContainer::ShowFileChooser() {
         }
     });
 
-    auto filter_all = Gtk::FileFilter::create();
-    filter_all->set_name("All files (*.*)");
-    filter_all->add_pattern("*.*");
-    dlg->add_filter(filter_all);
-
     dlg->run();
 }