bpo-43745: Actually updates Windows release to OpenSSL 1.1.1k. (GH-25213)

Earlier releases were mislabelled and included 1.1.1i again.
The tag/directory name is updated to ensure that builds get the fresh bits. However, the openssl-bin-1.1.1k tag in the repository has been forcibly updated, so fresh builds will be fine even without this change.