Revert "revert for ubuntu 18.04" for 4.0.1 release

This reverts commit 2b19c8f.

Author: kay-kim

source/includes/fact-platform-x86_64.rst

@@ -95,6 +95,11 @@
      - |checkmark|
      - |checkmark|
      - |checkmark|
+   * - Ubuntu 18.04
+     - |checkmark|
+     - 
+     - 
+     -
 
    * - Windows Vista
      -

source/includes/steps-install-mongodb-enterprise-on-ubuntu.yaml

@@ -24,6 +24,11 @@ action:
 
            echo "deb [ arch=amd64,arm64,ppc64el,s390x ] http://repo.mongodb.com/apt/ubuntu xenial/mongodb-enterprise/{+package-branch+} multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-enterprise.list
 
+      Ubuntu 18.04
+        .. code-block:: sh
+
+           echo "deb [ arch=amd64 ] http://repo.mongodb.com/apt/ubuntu bionic/mongodb-enterprise/{+package-branch+} multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-enterprise.list
+
   - pre: |
       If you'd like to install MongoDB Enterprise packages from a
       particular :ref:`release series <release-version-numbers>` such as

source/includes/steps-install-mongodb-on-ubuntu.yaml

@@ -31,6 +31,12 @@ action:
       .. code-block:: sh
 
          echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu xenial/mongodb-org/{+package-branch+} multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-{+version+}.list
+
+    Ubuntu 18.04
+      .. code-block:: sh
+
+         echo "deb [ arch=amd64 ] https://repo.mongodb.org/apt/ubuntu bionic/mongodb-org/{+package-branch+} multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-{+version+}.list
+
 ---
 title: Reload local package database.
 stepnum: 3

source/release-notes/4.0.txt

@@ -774,6 +774,8 @@ Platform Support
 
   - :doc:`Debian 9 "Stretch" </tutorial/install-mongodb-on-debian>`
 
+  - :doc:`Ubuntu 18.04 </tutorial/install-mongodb-on-ubuntu>`
+
 - MongoDB 4.0 (Community) adds support for:
 
   - s390x RHEL 6.x