Fix 1473 and add vca_model_config_* to lcm charm

Changes in all operator charms:
- Optimize deps for tox environments
- Add import-order-style to flake8
- Optimize .jujuignore to reduce the size of charm artifacts
OSM LCM charm:
- Added vca_model_config_* options
Added bundle example for using a bundle
Updated the bundles and pin the new versions in the installer

Change-Id: Ic6591354fa5d1b5f43383215b2f0df13eb28ce67
Signed-off-by: David Garcia <david.garcia@canonical.com>
diff --git a/installers/charm/prometheus/src/charm.py b/installers/charm/prometheus/src/charm.py
index 3d72cac..47533dd 100755
--- a/installers/charm/prometheus/src/charm.py
+++ b/installers/charm/prometheus/src/charm.py
@@ -22,30 +22,26 @@
 
 # pylint: disable=E0213
 
-import logging
-from typing import Optional, NoReturn
 from ipaddress import ip_network
+import logging
+from typing import NoReturn, Optional
+from urllib.parse import urlparse
 
 from ops.framework import EventBase
 from ops.main import main
-
 from opslib.osm.charm import CharmedOsmBase
-
+from opslib.osm.interfaces.prometheus import PrometheusServer
 from opslib.osm.pod import (
-    IngressResourceV3Builder,
-    FilesV3Builder,
     ContainerV3Builder,
+    FilesV3Builder,
+    IngressResourceV3Builder,
     PodSpecV3Builder,
 )
-
-
 from opslib.osm.validator import (
     ModelValidator,
     validator,
 )
 
-from opslib.osm.interfaces.prometheus import PrometheusServer
-from urllib.parse import urlparse
 
 logger = logging.getLogger(__name__)