attention-set: Fix typo in the documentation

Change-Id: I11b687b5179d2e68673006a8bc41d614fbe747fc
diff --git a/owners-autoassign/src/main/resources/Documentation/attention-set.md b/owners-autoassign/src/main/resources/Documentation/attention-set.md
index 7ad9a55..0ae7fa5 100644
--- a/owners-autoassign/src/main/resources/Documentation/attention-set.md
+++ b/owners-autoassign/src/main/resources/Documentation/attention-set.md
@@ -11,7 +11,7 @@
 a generic interface that can be used to customize Gerrit's default
 attention-set behaviour.
 
-## owner-api setup
+## owners-api setup
 
 Copy the `owners-api.jar` libModule into the $GERRIT_SITE/lib directory
 and add the following entry to `gerrit.config`: