DOCSP-34858 Select a cluster option for new sync job (#126)

* DOCSP-34858 select a cluster

* DOCSP-34858 typos

* DOCSP-34858 extra info

* DOCSP-34858 jasonfeedback

Author: jocelyn-mendez1

source/jobs/creating-jobs.txt

@@ -98,16 +98,43 @@ Steps
 
   .. step:: Enter the source MongoDB connection details 
 
-      On the :guilabel:`Connect Destination DB` form, input your 
-      :guilabel:`MongoDB connection string (URI)`.
+      To provide the MongoDB connection details, select an Atlas
+      cluster or provide a MongoDB connection string (URI). If you're :ref:`logged 
+      in with Atlas <rm-atlas-log-in>`, the default option is to :guilabel:`Select 
+      a cluster`. If you aren't logged in with Atlas, the :guilabel:`Select a cluster` 
+      option is disabled.
 
-      If you leave any of the form fields for :guilabel:`Database`, :guilabel:`Username`, 
-      or :guilabel:`Password` blank, the values specified in the URI are used.
+      .. tabs::
 
-      Click :guilabel:`Connect`.
+         .. tab:: Select a cluster
+            :tabid: select-atlas-cluster
+
+            On the :guilabel:`Connect Destination DB` form, select an :guilabel:`Atlas Cluster` 
+            from the drop-down. Clusters are displayed in a three-level hierarchy: 
+            :guilabel:`Organization` > :guilabel:`Project` > :guilabel:`Cluster`, 
+            organized alphabetically. Only the first 100 clusters you are authorized to 
+            access are shown.
+
+            If you leave any of the form fields for :guilabel:`Database`, :guilabel:`Username`, 
+            or :guilabel:`Password` blank, the values from the Atlas cluster's metadata 
+            are used.
+
+            Click :guilabel:`Connect`.
+
+         .. tab:: Enter MongoDB URI
+            :tabid: enter-mongodb-uri
 
-  .. step:: Select your migration options
 
+            On the :guilabel:`Connect Destination DB` form, input your 
+            :guilabel:`MongoDB connection string (URI)`.
+
+            If you leave any of the form fields for :guilabel:`Database`, :guilabel:`Username`, 
+            or :guilabel:`Password` blank, the values specified in the URI are used.
+
+            Click :guilabel:`Connect`.
+
+  .. step:: Select your migration options
+   
       On the :guilabel:`Migration Options` form, select your 
       :guilabel:`Migration Options`: