Finish off backend tests

tests/base.py

@@ -0,0 +1,16 @@
+import sys
+
+from fastapi.testclient import TestClient
+
+sys.path.append("..")
+
+from src.main import app, get_db
+from tests.config.database import override_get_db
+
+app.dependency_overrides[get_db] = override_get_db
+
+client = TestClient(app)
+
+username = "user1"
+password = "password"
+avatar = "lion"