[range.single.view] Remove duplicate semicolon (#6040)

Author: hewillk

source/ranges.tex

@@ -2522,7 +2522,7 @@
 
 \indexlibraryctor{single_view}%
 \begin{itemdecl}
-constexpr explicit single_view(const T& t) requires @\libconcept{copy_constructible}@<T>;;
+constexpr explicit single_view(const T& t) requires @\libconcept{copy_constructible}@<T>;
 \end{itemdecl}
 
 \begin{itemdescr}