Remove: setting "no_http_content_downloads" (#12058)

As we now use HTTPS, it is very likely this will work on most systems.
For systems that do have HTTPS blocked, it will fail instantly,
and it will fallback to TCP anyway. That makes this setting no longer
very useful.

src/settings_type.h

@@ -330,7 +330,6 @@ struct NetworkSettings {
 	uint8_t       min_active_clients;                       ///< minimum amount of active clients to unpause the game
 	bool        reload_cfg;                               ///< reload the config file before restarting
 	std::string last_joined;                              ///< Last joined server
-	bool        no_http_content_downloads;                ///< do not do content downloads over HTTP
 	UseRelayService use_relay_service;                    ///< Use relay service?
 	ParticipateSurvey participate_survey;                 ///< Participate in the automated survey
 };