whitelist mmf_sa (#2028)

## Changes
whitelist mmf_sa

### Linked issues
Progresses #1901 

### Functionality 
None

### Tests
- [x] manually tested

Co-authored-by: Eric Vergnaud <[email protected]>

Author: ericvergnaud

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

@@ -5572,6 +5572,9 @@
     "megatron.utils.pipeline": [],
     "megatron.visuals": []
   },
+  "mmf_sa": {
+    "mmf_sa": []
+  },
   "ml-dtypes": {
     "ml_dtypes": [],
     "ml_dtypes._finfo": [],