test: unmark test-zlib.zlib-binding.deflate flaky

PR-URL: #21109
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: apapirovski

test/async-hooks/async-hooks.status

@@ -9,7 +9,6 @@ prefix async-hooks
 [$system==win32]
 
 [$system==linux]
-test-zlib.zlib-binding.deflate: PASS,FLAKY
 
 [$system==macos]