docs/config: set code block language to ini

Change-Id: I9ac6be5c61c4b5c4cdedd3a9cfa89d4fba930e17

src/main/resources/Documentation/config.md

diff --git a/src/main/resources/Documentation/config.md b/src/main/resources/Documentation/config.md
index 913180b..63536af 100644
--- a/src/main/resources/Documentation/config.md
+++ b/src/main/resources/Documentation/config.md
@@ -364,7 +364,7 @@
 
 A typical visibility configuration will look like:
 
-```
+```ini
   [plugin "its-jira"]
     visibilityType = role
     visibilityValue = Dev