maint: remove steam verfification

src/client/component/steam_proxy.cpp

@@ -209,11 +209,11 @@ namespace steam_proxy
 				switch (res)
 				{
 				case ownership_state::nosteam:
-					throw std::runtime_error("Steam must be running to play this game!");
+					break;
 				case ownership_state::unowned:
-					throw std::runtime_error("You must own the game on steam to play this mod!");
+					break;
 				case ownership_state::error:
-					throw std::runtime_error("Failed to verify ownership of the game!");
+					break;
 				case ownership_state::success:
 					break;
 				}