Increase postback timeout to six minutes, to help users posting large payloads

services/git-bridge/src/main/java/uk/ac/ic/wlgitbridge/snapshot/push/PostbackPromise.java

@@ -14,7 +14,7 @@ import java.util.concurrent.locks.ReentrantLock;
  */
 public class PostbackPromise {
 
-    private static int TIMEOUT_SECONDS = 60 * 3;
+    private static int TIMEOUT_SECONDS = 60 * 6;
 
     private final String postbackKey;
     private final ReentrantLock lock;