doc: remove comma, related to commit 92d31085

Reported-by: Peter Eisentraut

Discussion: https://postgr.es/m/750b8832-d123-7f9b-931e-43ce8321b2d7@2ndquadrant.com

Backpatch-through: 9.5

doc/src/sgml/func.sgml

@@ -732,7 +732,7 @@
    </table>
 
    <para>
-    The bitwise operators work only on integral data types, and are also
+    The bitwise operators work only on integral data types and are also
     available for the bit
     string types <type>bit</type> and <type>bit varying</type>, as
     shown in <xref linkend="functions-bit-string-op-table"/>.