Removed legacy code function

tests/legacy/README.md

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+# Legacy Tests
+
+This are tests which had been written for old code, but which had been modified to test restructured new code.
+
+They shouldn't have high impacts on the stability of the system and propably could be deleted.

tests/legacy/test_configuration_filters.py

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+import unittest
+import sys
+import os
+
+sys.path.insert(
+    0,
+    os.path.abspath(
+        os.path.join(os.path.dirname(__file__), "../../")
+    ),
+)
+
+from filter_plugins.get_app_conf import AppConfigKeyError, get_app_conf
+
+def is_feature_enabled(applications: dict, feature: str, application_id: str) -> bool:
+    """
+    Wrapper for compatibility: Return True if applications[application_id].features[feature] is truthy.
+    """
+    return bool(get_app_conf(applications, application_id, f"features.{feature}", strict=False))
+
+
+class TestConfigurationFilters(unittest.TestCase):
+    def setUp(self):
+        # Sample applications data for testing
+        self.applications = {
+            'app1': {
+                'features': {
+                    'oauth2': True,
+                },
+            },
+            'app2': {
+                # no features or csp defined
+            },
+        }
+
+    # Tests for is_feature_enabled
+    def test_is_feature_enabled_true(self):
+        self.assertTrue(is_feature_enabled(self.applications, 'oauth2', 'app1'))
+
+    def test_is_feature_enabled_false_missing_feature(self):
+        self.assertFalse(is_feature_enabled(self.applications, 'nonexistent', 'app1'))
+
+    def test_is_feature_enabled_false_missing_app(self):
+         with self.assertRaises(Exception):
+            is_feature_enabled(self.applications, 'oauth2', 'unknown_app')
+
+if __name__ == '__main__':
+    unittest.main()