ciecplib 0.8.1

Patch release

Changes:

-   [https://git.ligo.org/computing/software/ciecplib/-/merge_requests/142]
    Replace usage of `datetime.utcnow()` with `datetime.now(UTC)`
-   [https://git.ligo.org/computing/software/ciecplib/-/merge_requests/146]
    Support new timezone-aware datetime representations in cryptography
-   [https://git.ligo.org/computing/software/ciecplib/-/merge_requests/150]
    Specify timeout for `get_idps` request

For full details of this release, see
<https://git.ligo.org/computing/software/ciecplib/-/releases/0.8.1>