v1.3.13

Fixed issues

• MARATHON-4802 - Constraint migration was not really implemented. This commit makes sure that it is fully implemented. During migration some constraints get sanitized. For instance, ["field", "UNIQUE", "value"] gets transformed to ["field", "UNIQUE"] because the UNIQUE constraint should not have any value. In addition to that the validation of CLUSTER is relaxed, because it doesn't require a value, and such a constraint did not pass the validation before.
• PR #5487 - Handle socket timeout exception when forwarding requests to a leader.