Update README.md

Author: bsieber-mozilla

README.md

@@ -7,7 +7,7 @@ System to sync Bugzilla bugs to Jira issues.
 ### Caveats
 - The system accepts webhook events from Bugzilla
 - The events are transformed into Jira issues
-- The system POSTs an update to the see_also field of Bugzilla bugs
+- The system sets the `see_also` field of the Bugzilla bug with the URL to the Jira issue
 - Bugs' whiteboard tags are used to determine if they should be synchronized or ignored
 
 ## Action Configuration