pdf: shorten front page spacing

Author: changkun

pdf/en-us/meta/template.tex

@@ -176,7 +176,7 @@
 
   \noindent This work was written by \href{https://github.com/changkun}{Ou Changkun} and licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. \texttt{\small http://creativecommons.org/licenses/by-nc-nd/4.0/}
 
-  \vspace{7em}
+  \vspace{6em}
   \includegraphics{../../assets/cover-2nd-en}
 
 \end{center}