fix(helmbroker): flake8

Author: duanhongyi

rootfs/bin/test-style

@@ -6,4 +6,4 @@
 # fail hard and fast even on pipelines
 set -eou pipefail
 
-flake8 --show-source
+flake8 --show-source --exclude .venv,migrations

rootfs/helmbroker/broker.py

@@ -13,7 +13,7 @@
 
 from .meta import load_instance_meta, load_binding_meta
 from .utils import get_instance_path, get_chart_path, get_plan_path, \
-    get_addon_path, get_addon_name, get_addon_updateable, get_addon_bindable
+    get_addon_path, get_addon_updateable, get_addon_bindable
 from .tasks import provision, bind, deprovision, update
 from helmbroker.meta import load_addons_meta