Adding HA support for Keystone charm

Change-Id: I691154ef2952bc124d7ddb689e39455c213c2a4b
Signed-off-by: sousaedu <eduardo.sousa@canonical.com>
diff --git a/installers/charm/keystone/requirements.txt b/installers/charm/keystone/requirements.txt
index 10ecdcd..5a4c0af 100644
--- a/installers/charm/keystone/requirements.txt
+++ b/installers/charm/keystone/requirements.txt
@@ -11,4 +11,5 @@
 #     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 #     See the License for the specific language governing permissions and
 #     limitations under the License.
+cryptography
 ops