Better handle headless

[armchairancap]

It's not necessary in this case, when we want to run headless (in iframe). -s may work, so no patch should be necessary. But for what it's worth this is where it happens.

tribler  | INFO:DownloadManager:Checkpoints are loaded
tribler  | ===> Request host and IP:  127.0.0.1:3100 127.0.0.1
tribler  | ERROR:pystray._base:Failed to dock icon
tribler  | Traceback (most recent call last):
tribler  |   File "/home/user/.local/lib/python3.10/site-packages/pystray/_xorg.py", line 162, in _update_icon
tribler  |     self._assert_docked()
tribler  |   File "/home/user/.local/lib/python3.10/site-packages/pystray/_xorg.py", line 395, in _assert_docked
tribler  |     assert self._systray_manager
tribler  | AssertionError
tribler  | ERROR:pystray._base:Failed to dock icon
tribler  | Traceback (most recent call last):
tribler  |   File "/home/user/.local/lib/python3.10/site-packages/pystray/_xorg.py", line 143, in _show
tribler  |     self._assert_docked()
tribler  |   File "/home/user/.local/lib/python3.10/site-packages/pystray/_xorg.py", line 395, in _assert_docked
tribler  |     assert self._systray_manager
tribler  | AssertionError