toolchain: run isort on it

BUG=b:229665884
TEST=`cros lint` is clean

Change-Id: Ie343654b19034b84d6e0b9c9f88d103bda2abb6d
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/3629677
Tested-by: Mike Frysinger <vapier@chromium.org>
Reviewed-by: Ryan Beltran <ryanbeltran@chromium.org>
Commit-Queue: Ryan Beltran <ryanbeltran@chromium.org>
Auto-Submit: Mike Frysinger <vapier@chromium.org>
diff --git a/api/controller/toolchain.py b/api/controller/toolchain.py
index 7978922..5480e16 100644
--- a/api/controller/toolchain.py
+++ b/api/controller/toolchain.py
@@ -18,6 +18,7 @@
 from chromite.lib import toolchain_util
 from chromite.service import toolchain
 
+
 # TODO(b/229665884): Move the implementation details for most/all endpoints to:
 #   chromite/services/toolchain.py
 # This migration has been done for linting endpoints but not yet for others.