(DOCSP-7376): Fixing x.509 mongo connection command

Author: jeff-allen-mongo

source/includes/steps-connect-to-x509-deployment.yaml

@@ -76,9 +76,21 @@ content: |
   Once you have created your X.509 user, try to connect to the
   deployment using the mongo Shell:
 
-  .. code-block:: sh
+  .. tabs::
+  
+     .. tab:: MongoDB 4.2
+        :tabid: mdb-4-2
+
+        .. code-block:: sh
+
+           mongo --host {host} --tls --tlsCAFile /var/run/secrets/kubernetes.io/serviceaccount/ca.crt --tlsCertificateKeyFile x509-full.pem --authenticationMechanism MONGODB-X509 --authenticationDatabase '$external'
+
+     .. tab:: MongoDB 4.0 and Older
+        :tabid: mdb-4-0-and-older
+
+        .. code-block:: sh
 
-     mongo --host {host} --ssl --sslCAFile /var/run/secrets/kubernetes.io/serviceaccount/ca.crt --sslPEMKeyFile x509-full.pem --authenticationMode MONGODB-X509
+           mongo --host {host} --ssl --sslCAFile /var/run/secrets/kubernetes.io/serviceaccount/ca.crt --sslPEMKeyFile x509-full.pem --authenticationMechanism MONGODB-X509 --authenticationDatabase '$external'
 
   .. note::