FIX: intersphinx routes (#569)

Author: mmcky

lectures/_config.yml

@@ -84,22 +84,22 @@ sphinx:
         - https://intro.quantecon.org/
         - null
       dle:
-        - https://quantecon.github.io/lecture-dle/
+        - https://dle.quantecon.org/
         - null
       dps:
-        - https://quantecon.github.io/lecture-dps/
+        - https://dps.quantecon.org/
         - null
       eqm:
-        - https://quantecon.github.io/lecture-eqm/
+        - https://eqm.quantecon.org/
         - null
       stats:
-        - https://quantecon.github.io/lecture-stats/
+        - https://stats.quantecon.org/
         - null
       tools:
-        - https://quantecon.github.io/lecture-tools-techniques/
+        - https://tools-techniques.quantecon.org/
         - null
       dynam:
-        - https://quantecon.github.io/lecture-dynamics/
+        - https://dynamics.quantecon.org/
         - null
     mathjax3_config:
       tex: