Update extensions.html (#1120)

Fixes typos in the linked URLs

docs/extensions.html

@@ -4,12 +4,12 @@ layout: default
 route: extensions
 extensions:
 - name: bulma-checkradio
-  url: https://wikiki.github.io/bulma-extensions/chekcradio
+  url: https://wikiki.github.io/bulma-extensions/checkradio
   slug: bulma-checkradio
   width: 758
   height: 67
 - name: bulma-switch
-  url: https://wikiki.github.io/bulma-extensions/siwtch
+  url: https://wikiki.github.io/bulma-extensions/switch
   slug: bulma-switch
   width: 1113
   height: 178