Pull request: fix edit static lease

Updates #6534

Squashed commit of the following:

commit 1ca6cdc37a865ff0beab2d1f4fb0d44528bd4df3
Author: Ildar Kamalov <ik@adguard.com>
Date:   Wed Dec 20 15:41:27 2023 +0300

    ADG-7889 fix edit static lease

client/src/reducers/dhcp.js

@@ -128,7 +128,8 @@ const dhcp = handleActions(
             const newState = {
                 ...state,
                 isModalOpen: !state.isModalOpen,
-                leaseModalConfig: payload,
+                modalType: payload?.type || '',
+                leaseModalConfig: payload?.config,
             };
             return newState;
         },