replace angle brackets

Co-authored-by: Henrik Tidefelt <henrikt@wolfram.com>

chapters/packages.tex

@@ -382,9 +382,9 @@ \section{Multilingual Descriptions}\label{multilingual-descriptions}
 In the body, directly following the header, for each descriptive text there is an entry of the form
 \begin{lstlisting}
 #: $\mathit{filename}$:$\mathit{lineNumber}$
-msgctxt "<context identifier>"
-msgid "<descriptive text>"
-msgstr "<translation>"
+msgctxt $\mathit{messageContext}$
+msgid $\mathit{messageIdentifier}$
+msgstr $\mathit{messageTranslation}$
 \end{lstlisting}
 \end{nonnormative}