DOC: fix references to the section about time format.

Time format is documented in section 2.4, not 2.2.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index d7ffd3f..7cac3ca 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -8519,7 +8519,7 @@
                was last created, refreshed or matched. The expiration delay is
                defined using the standard time format, similarly as the various
                timeouts. The maximum duration is slightly above 24 days. See
-               section 2.2 for more information. If this delay is not specified,
+               section 2.4 for more information. If this delay is not specified,
                the session won't automatically expire, but older entries will
                be removed once full. Be sure not to use the "nopurge" parameter
                if not expiration delay is specified.
@@ -8667,7 +8667,7 @@
         # computed over a sliding window of 30 seconds.
         stick-table type ip size 1m expire 5m store gpc0,conn_rate(30s)
 
-  See also : "stick match", "stick on", "stick store-request", section 2.2
+  See also : "stick match", "stick on", "stick store-request", section 2.4
              about time format and section 7 about ACLs.