fix valign ... pdf seems to be slightly too large

workshops/latex/latex.tex

@@ -652,7 +652,7 @@
     \begin{column}{0.55\textwidth}
       % TODO vertical alignment
       \only<1>{\lstinputlisting[basicstyle=\tiny\ttfamily]{examples/preamble.tex}}
-      \only<2>{\includegraphics[width=0.8\textwidth]{examples/preamble.pdf}}
+      \only<2>{\vspace{-.5em}\includegraphics[width=0.8\textwidth]{examples/preamble.pdf}}
     \end{column}
   \end{columns}
 \end{frame}