Fix the omission in docs.

Amit Kapila · Amit Kapila · commit e8ba27a4ce7f · 2018-11-15T11:09:15.000+05:30
Commit 5373bc2 has added type for background workers but forgot to update at one place in the documentation. Reported-by: John Naylor Author: John Naylor Reviewed-by: Amit Kapila Backpatch-through: 11 Discussion: https://postgr.es/m/CAJVSVGVmvgJ8Lq4WBxC3zV5wf0txdCqRSgkWVP+jaBF=HgWscA@mail.gmail.com
diff --git a/doc/src/sgml/monitoring.sgml b/doc/src/sgml/monitoring.sgml
@@ -804,10 +804,14 @@ postgres   27093  0.0  0.0  30096  2752 ?        Ss   11:34   0:00 postgres: ser
      <entry><type>text</type></entry>
      <entry>Type of current backend. Possible types are
       <literal>autovacuum launcher</literal>, <literal>autovacuum worker</literal>,
-      <literal>background worker</literal>, <literal>background writer</literal>,
+      <literal>logical replication launcher</literal>,
+      <literal>logical replication worker</literal>,
+      <literal>parallel worker</literal>, <literal>background writer</literal>,
       <literal>client backend</literal>, <literal>checkpointer</literal>,
       <literal>startup</literal>, <literal>walreceiver</literal>,
       <literal>walsender</literal> and <literal>walwriter</literal>.
+      In addition, background workers registered by extensions may have
+      additional types.
      </entry>
     </row>
    </tbody>
