Repair a duplicate label and some obsolete uses of \setindexsubitem.
diff --git a/Doc/lib/libunittest.tex b/Doc/lib/libunittest.tex
index ed386de..fa198c7 100644
--- a/Doc/lib/libunittest.tex
+++ b/Doc/lib/libunittest.tex
@@ -91,7 +91,7 @@
 \end{seealso}
 
 
-\subsection{Basic example \label{minimal-example}}
+\subsection{Basic example \label{unittest-minimal-example}}
 
 The \module{unittest} module provides a rich set of tools for
 constructing and running tests.  This section demonstrates that a