Whitelists dbl-tempo (#2791)

## Changes
Whitelists dbl-tempo

### Linked issues
Partly resolve #1931

Author: pritishpai

src/databricks/labs/ucx/source_code/known.json

@@ -2486,6 +2486,13 @@
     "dbignite.readers": [],
     "dbignite.version": []
   },
+  "dbl-tempo": {
+    "tempo": [],
+    "tempo.interpol": [],
+    "tempo.intervals": [],
+    "tempo.resample": [],
+    "tempo.utils": []
+  },
   "dbldatagen": {
     "dbldatagen": [],
     "dbldatagen._version": [],
@@ -30131,4 +30138,4 @@
     "zipp.compat.py310": [],
     "zipp.glob": []
   }
-}
+}