Try multi-line files

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Author: AA-Turner

Tools/build/mypy.ini

@@ -1,5 +1,7 @@
 [mypy]
-files = Tools/build/generate_sbom.py, Tools/build/compute-changes.py
+files =
+    Tools/build/compute-changes.py,
+    Tools/build/generate_sbom.py
 pretty = True
 
 # Make sure Python can still be built