feat: Drop apt install bcrypt (#148)

Currently, Dex Charm is doing apt install. Update this logic to ensure
the Dex Charm can work in an airgapped environment.

Closes #100 

Signed-off-by: Phoevos Kalemkeris <phoevos.kalemkeris@canonical.com>

src/charm.py

@@ -3,11 +3,11 @@
 # See LICENSE file for licensing details.
 
 import logging
-import subprocess
 from random import choices
 from string import ascii_letters
 from uuid import uuid4
 
+import bcrypt
 import yaml
 from charmed_kubeflow_chisme.exceptions import ErrorWithStatus
 from charms.grafana_k8s.v0.grafana_dashboard import GrafanaDashboardProvider
@@ -20,13 +20,6 @@
 from ops.pebble import Layer
 from serialized_data_interface import NoCompatibleVersions, NoVersionsListed, get_interface
 
-try:
-    import bcrypt
-except ImportError:
-    subprocess.check_call(["apt", "update"])
-    subprocess.check_call(["apt", "install", "-y", "python3-bcrypt"])
-    import bcrypt
-
 METRICS_PATH = "/metrics"
 METRICS_PORT = "5558"