Added sleep

[Alopalao]

Closes #295

Summary

Best guess is that of_lldp does not free vlans fast enough. So when a switch is deleted, vlans appeared to be used.

Local Tests

End-to-End Tests

From gitlab

============================= test session starts ==============================
platform linux -- Python 3.11.2, pytest-8.1.1, pluggy-1.4.0
rootdir: /builds/amlight/kytos-end-to-end-tester/kytos-end-to-end-tests
plugins: rerunfailures-13.0, timeout-2.2.0, anyio-4.3.0
collected 261 items
tests/test_e2e_01_kytos_startup.py ..                                    [  0%]
tests/test_e2e_05_topology.py ....................                       [  8%]
tests/test_e2e_10_mef_eline.py ..........ss.....x.....x................  [ 23%]
tests/test_e2e_11_mef_eline.py ......                                    [ 26%]
tests/test_e2e_12_mef_eline.py .....Xx.                                  [ 29%]
tests/test_e2e_13_mef_eline.py ....Xs.s.....Xs.s.XXxX.xxxx..X........... [ 44%]
.                                                                        [ 45%]
tests/test_e2e_14_mef_eline.py x                                         [ 45%]
tests/test_e2e_15_mef_eline.py .....                                     [ 47%]
tests/test_e2e_16_mef_eline.py .                                         [ 47%]
tests/test_e2e_20_flow_manager.py .....................                  [ 55%]
tests/test_e2e_21_flow_manager.py ...                                    [ 57%]
tests/test_e2e_22_flow_manager.py ...............                        [ 62%]
tests/test_e2e_23_flow_manager.py ..............                         [ 68%]
tests/test_e2e_30_of_lldp.py ....                                        [ 69%]
tests/test_e2e_31_of_lldp.py ...                                         [ 70%]
tests/test_e2e_32_of_lldp.py ...                                         [ 72%]
tests/test_e2e_40_sdntrace.py ..............                             [ 77%]
tests/test_e2e_41_kytos_auth.py ........                                 [ 80%]
tests/test_e2e_42_sdntrace.py ..                                         [ 81%]
tests/test_e2e_50_maintenance.py ............................            [ 91%]
tests/test_e2e_60_of_multi_table.py .....                                [ 93%]
tests/test_e2e_70_kytos_stats.py ........                                [ 96%]
tests/test_e2e_80_pathfinder.py ss......                                 [100%]