fix typo

Signed-off-by: lilinjie <lilinjie@uniontech.com>

Author: uniontech-lilinjie

HISTORY.rst

@@ -28,7 +28,7 @@ FUTURE: TBD
 1.2.0: 2020-02-18
 -----------------
 
-- Add support for specifing an explicit GSSAPI mech
+- Add support for specifying an explicit GSSAPI mech
 
 1.1.1: 2020-02-18
 -----------------