[set.cons] Fix grammar typo

Author: jensmaurer

source/containers.tex

@@ -10610,7 +10610,7 @@
 \begin{itemdescr}
 \pnum
 \effects
-Constructs an empty \tcode{set} using the specified comparison objects and allocator.
+Constructs an empty \tcode{set} using the specified comparison object and allocator.
 
 \pnum
 \complexity