Thinko repair.

Doc/lib/libdoctest.tex

@@ -315,7 +315,7 @@ Some details you should read once, but won't need to remember:
 
 \subsection{Option Flags and Directives\label{doctest-options}}
 
-A number of option flags control various aspects of doctest's comparison
+A number of option flags control various aspects of doctest's
 behavior.  Symbolic names for the flags are supplied as module constants,
 which can be or'ed together and passed to various functions.  The names
 can also be used in doctest directives (see below).