How can I broaden a figure including caption?

I’m tring to extend a figure including the caption horizontally beyond the \textwidth. I tried wrapping the figure in a wider \makebox, but that does not work.

\documentclass{article}
\usepackage[demo]{graphicx}
\usepackage[english]{babel}
\usepackage{tikz}
\usepackage[utf8]{inputenc}
\usepackage{blindtext}
\usepackage{titlesec}
\begin{document}

\makebox[1.2\textwidth][c]{
\begin{figure}
\centering
\renewcommand{\arraystretch}{3}
\begin{tabular*}{\textwidth}{@{}ccc@{}}
  \includegraphics[width=0.31\linewidth,height=2cm]{dummy} &
        \includegraphics[width=0.31\linewidth,height=2cm]{dummy}&
        \includegraphics[width=0.31\linewidth,height=2cm]{dummy}\\
    \includegraphics[width=0.31\linewidth,height=2cm]{dummy} &
        \includegraphics[width=0.31\linewidth,height=2cm]{dummy}&
        \includegraphics[width=0.31\linewidth,height=2cm]{dummy}
\end{tabular*}
\end{figure}
}

\blindtext

\end{document}