enable cudf-java docs (#728)

enable cudf-java

Author: AyodeAwe

ci/customization/projects-to-versions.json

@@ -25,7 +25,8 @@
     "nightly": "26.02"
   },
   "cudf-java": {
-    "legacy": "25.10"
+    "legacy": "25.10",
+    "stable": "25.12"
   },
   "cucim": {
     "legacy": "25.10",