lint: scripts: sort imports

After configuring sort behavior in isort.cfg, run `./scripts/isort`
on all the scripts/ modules in the tree.

BUG=b:187788732
TEST=`cros lint` is clean

Change-Id: Ida93e1a699eb6ee14adddb9f98bfca4392786143
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3615054
Auto-Submit: Mike Frysinger <vapier@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Sloan Johnson <sloanjohnson@google.com>
Commit-Queue: Sloan Johnson <sloanjohnson@google.com>
diff --git a/scripts/cros_generate_update_payload_unittest.py b/scripts/cros_generate_update_payload_unittest.py
index 8aa65fe..ddf5aa0 100644
--- a/scripts/cros_generate_update_payload_unittest.py
+++ b/scripts/cros_generate_update_payload_unittest.py
@@ -7,9 +7,9 @@
 from chromite.lib import cros_test_lib
 from chromite.lib import partial_mock
 from chromite.lib.paygen import paygen_payload_lib
-
 from chromite.scripts import cros_generate_update_payload
 
+
 pytestmark = cros_test_lib.pytestmark_inside_only