Add git lfs pull to workflow.md (commaai#32914)

old-commit-hash: edd042f

docs/WORKFLOW.md

@@ -9,6 +9,7 @@ Most development happens on normal Ubuntu workstations, and not in cars or direc
 ```bash
 # get the latest stuff
 git pull
+git lfs pull
 git submodule update --init --recursive
 
 # update dependencies