Fix server client read/write not returning when encryption is used.

When the client created by the server reads or writes to an attribute and it triggers a pairing action the task will not be released because the client does not get the event.
This passes the event to the client to prevent the task from being hung.

src/NimBLEServer.cpp

@@ -530,6 +530,11 @@ int NimBLEServer::handleGapEvent(ble_gap_event* event, void* arg) {
             }
 
             pServer->m_pServerCallbacks->onAuthenticationComplete(peerInfo);
+# if CONFIG_BT_NIMBLE_ROLE_CENTRAL
+            if (pServer->m_pClient && pServer->m_pClient->m_connHandle == event->enc_change.conn_handle) {
+                NimBLEClient::handleGapEvent(event, pServer->m_pClient);
+            }
+# endif
             break;
         } // BLE_GAP_EVENT_ENC_CHANGE