lower the priority of application task of a2dp demo

Closes https://github.com/espressif/esp-idf/issues/9192

examples/bluetooth/bluedroid/classic_bt/a2dp_sink/main/bt_app_core.c

@@ -151,7 +151,7 @@ bool bt_app_work_dispatch(bt_app_cb_t p_cback, uint16_t event, void *p_params, i
 void bt_app_task_start_up(void)
 {
     s_bt_app_task_queue = xQueueCreate(10, sizeof(bt_app_msg_t));
-    xTaskCreate(bt_app_task_handler, "BtAppTask", 3072, NULL, configMAX_PRIORITIES - 3, &s_bt_app_task_handle);
+    xTaskCreate(bt_app_task_handler, "BtAppTask", 3072, NULL, 10, &s_bt_app_task_handle);
 }
 
 void bt_app_task_shut_down(void)

examples/bluetooth/bluedroid/classic_bt/a2dp_source/main/bt_app_core.c

@@ -115,7 +115,7 @@ bool bt_app_work_dispatch(bt_app_cb_t p_cback, uint16_t event, void *p_params, i
 void bt_app_task_start_up(void)
 {
     s_bt_app_task_queue = xQueueCreate(10, sizeof(bt_app_msg_t));
-    xTaskCreate(bt_app_task_handler, "BtAppTask", 2048, NULL, configMAX_PRIORITIES - 3, &s_bt_app_task_handle);
+    xTaskCreate(bt_app_task_handler, "BtAppTask", 2048, NULL, 10, &s_bt_app_task_handle);
 }
 
 void bt_app_task_shut_down(void)