DOC: management: add missing dot in 9.4.1

The 9.4.1 chapter is missing the dot at the end of the chapter numbers.
Which broke the haproxy-dconv html generation.

No backport needed, 2.6 only.
diff --git a/doc/management.txt b/doc/management.txt
index 15bf82c..f0fdcc0 100644
--- a/doc/management.txt
+++ b/doc/management.txt
@@ -3719,7 +3719,7 @@
    # haproxy -W -S /tmp/master-socket,level,user -f test1.cfg
 
 
-9.4.1 Master CLI commands
+9.4.1. Master CLI commands
 --------------------------
 
 @<[!]pid>