fix missing ) in 2012/endoh2/README.md

Ran `bin/readme2index.sh -v 1 2012/endoh2` to perform the above.

2012/endoh2/index.html

@@ -421,7 +421,7 @@ machine</a> emulation?</p>
 <p>Yeah, “Again”. Sorry. But I don’t feel guilty or uncomfortable.</p>
 <p>This entry is based on ‘over-used themes’ such as self reproducing
 program and <a href="https://en.wikipedia.org/wiki/Pi">pi</a> or
-<a href="https://en.wikipedia.org/wiki/E_(mathematical_constant(">e</a> computation. I
+<a href="https://en.wikipedia.org/wiki/E_(mathematical_constant)">e</a> computation. I
 know you’re tired of them.</p>
 <p>But have you ever seen them <strong>all-in-one</strong>?</p>
 <h3 id="what-it-is">What it is</h3>