Fix typo in documentation

gpdb-doc/dita/admin_guide/highavail/topics/g-overview-of-segment-mirroring.xml

@@ -12,7 +12,7 @@
             unavailable, it changes the role of its mirror segment to primary segment and the role
             of the unavailable primary segment to mirror segment. Transactions in progress when the
             failure occurred roll back and must be restarted. The administrator must then recover
-            the mirror segment, allow the mirror to syncronize with the current primary segment, and
+            the mirror segment, allow the mirror to synchronize with the current primary segment, and
             then exchange the primary and mirror segments so they are in their preferred roles.</p>
         <p>If segment mirroring is not enabled, the Greenplum Database system shuts down if a
             segment instance fails. Administrators must manually recover all failed segments before