check-presubmit: move `get_from_pip` under `get_pip` check

mypy was complaining about the `pip + ["show", "mypy"]` here, since
`pip`'s inferred type is `Optional[_]`. Moving this function's
definition below the `if not pip` check assures `mypy` that this
function is only ever called if `pip` has a value.

BUG=b:308443233
TEST=repo upload

Change-Id: Iecef039d64bc5102d4d4171e85d39914119df1e0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/4989913
Commit-Queue: George Burgess <gbiv@chromium.org>
Tested-by: George Burgess <gbiv@chromium.org>
Reviewed-by: Bob Haarman <inglorion@chromium.org>
1 file changed