Update README.md

Author: NikolasKomonen

README.md

@@ -51,7 +51,7 @@ The following settings are supported:
 Since 0.2.0:
 * `xml.server.vmargs`: Extra VM arguments used to launch the XML Language Server. Requires VS Code restart.
 
-More detailed info in [Wiki](https://github.com/redhat-developer/vscode-xml/wiki/Preferences).
+More detailed info in the [Wiki](https://github.com/redhat-developer/vscode-xml/wiki/Preferences).
 
 ## Contributing