DOCS-1021 fixing name of command in release notes

Author: Sam Kleinman

source/release-notes/2.4.txt

@@ -500,7 +500,7 @@ system are available for use in MongoDB:
 - SASL Support in :program:`mongod`, the :program:`mongo` shell, and C++ client library
   (driver.)
 
-- New :dbcommand:`saslBegin` and :dbcommand:`saslContinue`
+- New :dbcommand:`saslStart` and :dbcommand:`saslContinue`
   database commands.
 
 .. note::
@@ -583,7 +583,7 @@ In the 2.3 series, MongoDB adds the following database commands:
 .. leaving these undocumented at the moment, given changing use, and
    the fact that the previous section satisfies current requirements.
 
-.. dbcommand:: saslBegin
+.. dbcommand:: saslStart
 
 .. dbcommand:: saslContinue