Fix typos in example doc for task properties

Change-Id: I4c775fe66f462c387a4f56a5d8de7e9097b0b2ab
diff --git a/src/main/resources/Documentation/task.md b/src/main/resources/Documentation/task.md
index 8a75c0e..7a0cf1e 100644
--- a/src/main/resources/Documentation/task.md
+++ b/src/main/resources/Documentation/task.md
@@ -448,9 +448,9 @@
 
 Examples:
 ```
-    fail-hint = {$_name} needs to be fixed
-    fail-hint = {$_change_number} with {$_change_status} needs to be fixed
-    fail-hint = {$_change_id} on {$_change_project} and {$_change_branch} needs to be fixed
+    fail-hint = ${_name} needs to be fixed
+    fail-hint = ${_change_number} with ${_change_status} needs to be fixed
+    fail-hint = ${_change_id} on ${_change_project} and ${_change_branch} needs to be fixed
     changes = parentof:${_change_number} project:${_change_project} branch:${_change_branch}
 ```