no-std compatibility CI check failing

[redshiftzero]

CI failure here:

anyhow: FAILURE
  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/lib.rs

  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/backtrace.rs

  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/context.rs

  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/error.rs

  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/lib.rs

  - Source code contains an explicit `use std::` statement.
   --> /home/runner/.cargo/registry/src/index.crates.io-6f17d22bba15001f/anyhow-1.0.80/src/wrapper.rs

This will be fixed by penumbra-zone/penumbra#3675, but filing for awareness

[redshiftzero]

after merge of #53, this is no longer failing, so closing