refactor: move tests folder structure and update pytest commands (#2785)

* refactor: move tests folder to src/backend

* chore(Makefile): update pytest commands to run tests from the correct directory paths for unit and integration tests

* refactor: update file path in test_custom_component.py

The file path in the test_custom_component.py file has been updated to use the correct relative path to the component_multiple_outputs.py file. This change ensures that the test code can access the correct file and improves the reliability of the test.

src/backend/tests/unit/test_api_key.py

@@ -0,0 +1,45 @@
+import pytest
+from langflow.services.database.models.api_key import ApiKeyCreate
+
+
+@pytest.fixture
+def api_key(client, logged_in_headers, active_user):
+    api_key = ApiKeyCreate(name="test-api-key")
+
+    response = client.post("api/v1/api_key", data=api_key.model_dump_json(), headers=logged_in_headers)
+    assert response.status_code == 200, response.text
+    return response.json()
+
+
+def test_get_api_keys(client, logged_in_headers, api_key):
+    response = client.get("api/v1/api_key", headers=logged_in_headers)
+    assert response.status_code == 200, response.text
+    data = response.json()
+    assert "total_count" in data
+    assert "user_id" in data
+    assert "api_keys" in data
+    assert any("test-api-key" in api_key["name"] for api_key in data["api_keys"])
+    # assert all api keys in data["api_keys"] are masked
+    assert all("**" in api_key["api_key"] for api_key in data["api_keys"])
+
+
+def test_create_api_key(client, logged_in_headers):
+    api_key_name = "test-api-key"
+    response = client.post("api/v1/api_key", json={"name": api_key_name}, headers=logged_in_headers)
+    assert response.status_code == 200
+    data = response.json()
+    assert "name" in data and data["name"] == api_key_name
+    assert "api_key" in data
+    # When creating the API key is returned which is
+    # the only time the API key is unmasked
+    assert "**" not in data["api_key"]
+
+
+def test_delete_api_key(client, logged_in_headers, active_user, api_key):
+    # Assuming a function to create a test API key, returning the key ID
+    api_key_id = api_key["id"]
+    response = client.delete(f"api/v1/api_key/{api_key_id}", headers=logged_in_headers)
+    assert response.status_code == 200
+    data = response.json()
+    assert data["detail"] == "API Key deleted"
+    # Optionally, add a follow-up check to ensure that the key is actually removed from the database