Course information slides: add Matrix screenshot

- Sounds like a good idea to use Matrix even for on-site courses

Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>

slides/course-information/course-information.tex

@@ -54,17 +54,23 @@
 
 \begin{frame}
 \frametitle{Cooperate!}
-As in the Free Software and Open Source community,
-cooperation during practical labs is valuable in this training session:
-\begin{itemize}
-\item If you complete your labs before other people, don't hesitate to help
-other people and investigate the issues they face. The faster we progress as a
-group, the more time we have to explore extra topics.
-\item Explain what you understood to other participants when needed.
-It also helps to consolidate your knowledge.
-\item Don't hesitate to report potential bugs to your instructor.
-\item Don't hesitate to look for solutions on the Internet as well.
-\end{itemize}
+\begin{columns}
+\column{0.8\textwidth}
+  As in the Free Software and Open Source community,
+  cooperation during practical labs is valuable in this training session:
+  \begin{itemize}
+    \item Use the dedicated Matrix channel for this session
+    \item If you complete your labs before other people, don't hesitate to help
+          them and investigate the issues they face. The faster we progress as a
+          group, the more time we have to explore extra topics.
+    \item Explain what you understood to other participants when needed.
+          It also helps to consolidate your knowledge.
+    \item Don't hesitate to report potential bugs to your instructor.
+    \item Don't hesitate to look for solutions on the Internet as well.
+    \end{itemize}
+\column{0.2\textwidth}
+  \includegraphics[height=0.8\textheight]{slides/course-information/matrix-screenshot.png}
+\end{columns}
 \end{frame}
 
 \begin{frame}