Use MongoDB 4.0 on Xenial and EL7

Author: amanda11

roles/StackStorm.mongodb/vars/debian.yml

@@ -1,9 +1,10 @@
 # Set mongodb version to provided value or 3.6 if not specified
-mongodb_use_version: "{{ mongodb_version | default (mongodb36_version) }}"
+mongodb_use_version: "{{ mongodb_version | default (mongodb40_version) }}"
 # Extract mongodb "major.minor" version
 mongodb_major_minor_version: "{{ (mongodb_use_version|string)[:3] }}"
 # Use the following URL to find the key: https://www.mongodb.org/static/pgp/server-{{ mongodb_major_minor_version }}.asc
 mongodb_apt_keys:
   "3.2": "42F3E95A2C4F08279C4960ADD68FA50FEA312927"
   "3.4": "0C49F3730359A14518585931BC711F9BA15703C6"
   "3.6": "2930ADAE8CAF5059EE73BB4B58712A2291FA4AD5"
+  "4.0": "9DA31620334BD75D9DCB49F368818C72E52529D4"

roles/StackStorm.mongodb/vars/redhat_7.yml

@@ -4,6 +4,6 @@ mongo_dependencies:
       - python-pyasn1
       - python-ndg_httpsclient
 # Set mongodb version to provided value or 3.6 if not specified
-mongodb_use_version: "{{ mongodb_version | default (mongodb36_version) }}"
+mongodb_use_version: "{{ mongodb_version | default (mongodb40_version) }}"
 # Extract mongodb "major.minor" version
 mongodb_major_minor_version: "{{ (mongodb_use_version|string)[:3] }}"