Skip partial_data tests for elastic search for which it has not been …

…implemented yet.

tests/server/routers/test_partial_data.py

@@ -1,8 +1,15 @@
+import pytest
+
 from optimade.models import PartialDataResponse
+from optimade.server.config import CONFIG
 
 from ..utils import NoJsonEndpointTests
 
 
+@pytest.mark.skipif(
+    CONFIG.database_backend.value not in ("mongomock", "mongodb"),
+    reason="At the moment partial data is only supported for the MongoDB backend",
+)
 class TestPartialDataEndpoint(NoJsonEndpointTests):
     """Tests for /partial_data/<entry_id>"""
 
@@ -22,8 +29,7 @@ def test_property_ranges_link(get_good_response, client):
 
 
 def test_wrong_id_partial_data(check_error_response, client):
-    """If a non-supported versioned base URL is passed, `553 Version Not Supported` should be returned
-
+    """
     A specific JSON response should also occur.
     """
     test_id = "mpf_486"