Update acme-client from 2.0.9 to 2.0.11

What does this MR do and why?

Updates acme-client gem from 2.0.9 to 2.0.11, which enables us to use Faraday v2.

https://github.com/unixcharles/acme-client/compare/v2.0.9...v2.0.11

Previous one: !77534 (merged)

Part of #369862 (closed)

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