Revert "libz is a stub"

Revert "Allow libz to have stub even though it's not an LLNDK li..."

Revert submission 1312595-zlib_as_stub

Reason for revert: broke rvc-dev-plus-aosp
Reverted Changes:
I7c0a7f954:libz is a stub
If51a7e80f:libz provides stubs to Mainline modules.
I26417bb78:Allow libz to have stub even though it's not an LL...

Change-Id: I412132f8a17af4442c76b218f17135932ecf76e0
diff --git a/build/apex/art_apex_test.py b/build/apex/art_apex_test.py
index 92505b4..b97ac23 100755
--- a/build/apex/art_apex_test.py
+++ b/build/apex/art_apex_test.py
@@ -618,6 +618,7 @@
     # Check internal native library dependencies.
     self._checker.check_native_library('libcrypto')
     self._checker.check_native_library('libexpat')
+    self._checker.check_native_library('libz')
 
     # TODO(b/139046641): Fix proper 2nd arch checks. For now, just ignore these
     # directories.