use recurse_submodules cc action arg + remove working_directory cc action arg

[matt-codecov]

needed for codecov/umbrella#17

codecov/codecov-action#1780 adds a recurse_submodules arg to the action which adds the --recurse-submodules arg to git ls-files when the CLI is building the network section.

this is necessary for umbrella because, at least while we migrate, worker/shared/api are submodules. we want coverage data for apps/worker/tasks/base.py etc so we need git ls-files to recurse into submodules when we're building the network section for umbrella uploads