Put ingest reference time back in the correct place in test

Commit 4dbfaa9 moved the reference time calculation to after
the ingest.

python/lsst/daf/butler/registry/tests/_registry.py

@@ -2722,8 +2722,8 @@ def testSkipCalibs(self):
     def testIngestTimeQuery(self):
         butler = self.make_butler()
         registry = butler._registry
-        self.load_data(butler, "base.yaml", "datasets.yaml")
         dt0 = datetime.datetime.now(datetime.UTC)
+        self.load_data(butler, "base.yaml", "datasets.yaml")
         dt1 = datetime.datetime.now(datetime.UTC)
 
         datasets = list(registry.queryDatasets(..., collections=...))