Fixing issues with the WebUI and the optical cybersecurity module

This MR focuses on fixing the issues reported in two issues:

• Closes #57 (closed)
• Closes #102 (closed)

The changes are as follows:

• Version of the Flask package has been updated to fix the issues in the WebUI.
• The tests of the opticalattackdetector have been reworked to fix the issue.

The pipelines are here:

• Optical attack detector: https://labs.etsi.org/rep/tfs/controller/-/jobs/51936
• WebUI: https://labs.etsi.org/rep/tfs/controller/-/pipelines/4220

src/opticalattackdetector/tests/test_unitary.py

@@ -73,6 +73,6 @@ def test_detect_attack(
             request.service_id.service_uuid.uuid = str(uuid.uuid4())
             request.kpi_id.kpi_id.uuid = "1"
             optical_attack_detector_client.DetectAttack(request)
-            dbscanserving.assert_called_once()
+            dbscanserving.assert_called()
             monitoring.assert_called_once()
         mitigator.NotifyAttack.assert_called()