Put date at a better height over hrule

Adjust where the date sits under the signature, so that the date isn't
squashed down such that it touches the hrule line underneath it.

Context: I actually made this change on November 3rd, as part of
building a contract document that day.  However, I forgot to push the
change then, and later it was in the way when I needed to pull from
upstream.  Rather than create a merge commit, I just saved the patch
and re-applied it.  So if you're at OTS and you're wondering about the
motivation for this change, look for a contract build on 2020-11-03.

latex/contract.cls

@@ -87,7 +87,7 @@
   \begin{minipage}[t]{7cm}
   \begin{tabular}{@{}p{#1}@{}}
     \\[2\normalbaselineskip] \hrule \\[0pt]
-    {\small \textit{#2}} \\ {\small \textit{#3}} \\[2\normalbaselineskip] \\ #4 \hrule \\[0pt]
+    {\small \textit{#2}} \\ {\small \textit{#3}} \\[2\normalbaselineskip] \\ ~\raisebox{.3em}{#4} \hrule \\[0pt]
     {\small \textit{Date}}
   \end{tabular}
   \end{minipage}