Temporarily disable 25.06 cugraph docs (#590)

Author: raydouglass

_data/docs.yml

@@ -45,7 +45,7 @@ apis:
       # enable or disable links; 0 = disabled, 1 = enabled
       legacy: 1
       stable: 1
-      nightly: 1
+      nightly: 0
   cuxfilter:
     name: cuxfilter
     path: cuxfilter