Delete documentation for 'server_log' info item. This doesn't currently exist and hasn't existed for a while.

--
MOS_MIGRATED_REVID=96711367
diff --git a/site/docs/bazel-user-manual.html b/site/docs/bazel-user-manual.html
index 6cb740a..5ae68ab 100644
--- a/site/docs/bazel-user-manual.html
+++ b/site/docs/bazel-user-manual.html
@@ -3114,9 +3114,6 @@
     <code class='flag'>--output_user_root</code> options.
   </li>
 
-  <li><code>server_log</code>: the absolute path to the Bazel server's
-    log file; this contains useful information for debugging Bazel.
-  </li>
   <li><code>used-heap-size</code>,
       <code>committed-size</code>,
       <code>max-heap-size</code>: reports various JVM heap size