DOCSP 22683 - primary node failure in deleteMany (#1609)

* DOCSP-22688 adding primary node failure behavior to deleteMany

* DOCSP-22688 adding primary node failure behavior to deleteMany

* DOCSP-22683 small copy edit

Author: ltran-mdb

source/reference/method/db.collection.deleteMany.txt

@@ -149,6 +149,14 @@ Transactions
 
 .. |operation| replace:: :method:`db.collection.deleteMany()`
 
+Primary Node Failure
+~~~~~~~~~~~~~~~~~~~~
+
+:method:`db.collection.deleteMany()` deletes documents one at a time. 
+If the primary node fails during a :method:`db.collection.deleteMany()`
+operation, documents that were not yet deleted from secondary nodes are
+not deleted from the collection.
+
 Examples
 --------