internetradio: Set 'RADIO_ALLOW_CUSTOM_URLS' default to true

It's already up to the user ("Allow external sounds" in MTA settings, or "Allow other players speakers" checkbox in `internetradio` GUI)

[gameplay]/internetradio/config/ShRadioConfig.lua

@@ -7,7 +7,7 @@
 RADIO_CREATE_SPEAKER_DELAY = 3000
 RADIO_TOGGLE_SPEAKER_DELAY = 1500
 RADIO_DESTROY_SPEAKER_DELAY = 1500
-RADIO_ALLOW_CUSTOM_URLS = false
+RADIO_ALLOW_CUSTOM_URLS = true
 RADIO_STREAM_URL_MAX_LENGTH = 512
 RADIO_MAX_SOUND_DISTANCE = 65
 RADIO_STATIONS = {
@@ -95,4 +95,4 @@ RADIO_STATIONS = {
 	{"[Summer96] RadioRecord", "https://radiorecord.hostingradio.ru/summerparty96.aacp"},
 	{"[Dance] BAYERN Radio - Dance XXL", "http://stream.antenne.de:80/dance-xxl"},
 	{"[Dance] FunX Dance", "https://icecast.omroep.nl/funx-dance-bb-mp3"},
-}
+}