Exclude Alembic migrations from Black

These files are autogenerated with their own formats, so we don't want
to override that.

format

@@ -5,7 +5,7 @@ if ! which black &>/dev/null; then
     exit 1
 fi
 
-black .
+black --exclude api-daemon/migrations .
 ret=$?
 if [[ $ret -eq 0 ]]; then
     echo "Successfully formatted project!"