Update chapters/classes.tex

Co-authored-by: Elena Shmoylova <eshmoylova@users.noreply.github.com>

chapters/classes.tex

@@ -729,7 +729,7 @@ \subsection{Short Class Definitions}\label{short-class-definitions}
 \end{lstlisting}
 \end{example}
 
-\subsection{Combining base classes and other elements}\label{restriction-on-combining-base-classes-and-other-elements}\label{combining-base-classes-and-other-elements}
+\subsection{Combining Base Classes and Other Elements}\label{restriction-on-combining-base-classes-and-other-elements}\label{combining-base-classes-and-other-elements}
 
 It is not legal to combine other components or base classes with an extends from an array class, a class with non-empty \lstinline[language=grammar]!base-prefix!, a \firstuse{simple type} (\lstinline!Real!, \lstinline!Boolean!, \lstinline!Integer!, \lstinline!String! and enumeration types), or any class transitively extending from an array class, a class with non-empty \lstinline[language=grammar]!base-prefix!, or a simple type.