Remove an unmatched </li> tag. (#107)

Remove an extra </li> tag from index.php.

Co-authored-by: Kyle Brenneman <ksb@shodan>
diff --git a/index.php b/index.php
index 87454ea..e6a39a0 100644
--- a/index.php
+++ b/index.php
@@ -343,7 +343,6 @@
 </li>
 <li value=137> <a href="extensions/WL/EGL_WL_create_wayland_buffer_from_image.txt">EGL_WL_create_wayland_buffer_from_image</a>
 </li>
-</li>
 <li value=139> <a href="extensions/NV/EGL_NV_stream_consumer_eglimage.txt">EGL_NV_stream_consumer_eglimage</a>
 </li>
 </ol>