Remove zlib dependency, keep spz.

kring · kring · commit 153891f1adfc · 2025-10-17T15:55:41.000+11:00
diff --git a/extern/cesium-native b/extern/cesium-native
@@ -1 +1 @@
-Subproject commit 0892990a73e888b824be57f841d1561cf9652d96
+Subproject commit efb08a9c9447473aa036605ce5378b31e151751d
