fix: redirects the 'Getting Started' link to the right guide

Author: claymcleod

_data/navigation.yml

@@ -2,7 +2,7 @@ main:
   - title: "About"
     url: /about
   - title: "Getting Started"
-    url: https://docs.openwdl.org/overview.html
+    url: https://docs.openwdl.org/getting-started/quickstart.html
   - title: "Specification"
     url: /spec
   - title: "Documentation"