docs/config: correct section for association policy

The association policy was moved to the plugin section in
I1b0c62b840b72d82949c4b6b8a555b292f0cc0fc.

Change-Id: I362c7b3468acdb00cdb3f28dacab77662d9ef18a
diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index b9edaed..913180b 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -78,10 +78,13 @@
 Example:
 
 ```ini
+    [plugin "its-jira"]
+    enabled = true
+    association = SUGGESTED
+
     [commentLink "its-jira"]
     match = ([A-Z]+-[0-9]+)
     html = "<a href=\"http://jira.example.com/browse/$1\">$1</a>"
-    association = SUGGESTED
 ```
 
 Jira connectivity