Set omit_zlib=True to fix issue with io_bazel_rules_closure:
no such target '@io_bazel_rules_closure//:third_party/zlib.BUILD'

Upgrade io_bazel_rules_go to latest stable v0.18.6.

Include .inc files in the tink_headers archive. This is needed by the //examples/helloworld/cc:non_bazel_build_test.

PiperOrigin-RevId: 255372936