session: handle uuid parsing failure

runelite-client/src/main/java/net/runelite/client/SessionClient.java

@@ -60,8 +60,16 @@ class SessionClient
 			{
 				ResponseBody body = response.body();
 
-			InputStream in = body.byteStream();
+				InputStream in = body.byteStream();
-			return RuneLiteAPI.GSON.fromJson(new InputStreamReader(in, StandardCharsets.UTF_8), UUID.class);
+				try
+				{
+					return RuneLiteAPI.GSON.fromJson(new InputStreamReader(in, StandardCharsets.UTF_8), UUID.class);
+				}
+				catch (IllegalArgumentException ex)
+				{
+					ex.printStackTrace();
+					return null;
+				}
 			}
 		});
 	}