Update link in schema to our own doc page

Author: cderv

src/resources/schema/definitions.yml

@@ -1585,7 +1585,7 @@
             short: "The date format to use when displaying dates (e.g. d-M-yyy)."
             long: |
               The date format to use when displaying dates (e.g. d-M-yyy). 
-              Learn more about supported date formatting values [here](https://deno.land/[email protected]/datetime).
+              Learn more about supported date formatting values [here](https://quarto.org/docs/reference/dates.html).
       max-description-length:
         number:
           description: