sequoia-gpg-agent v0.6.1 tests fail on RHEL 9 with gnupg 2.3.3

I tried building sequoia-gpg-agent v0.6.1 (and rebuilding sq, chameleon, octopus with the new version so they pick up the fixes for gnupg 2.4 support), and noticed that there were new test failures on RHEL 9.

It looks like the tests that fail were added in v0.6.1, so it's hard to tell whether this worked before or was just silently broken.

failures:
---- import_ecc_scalars stdout ----
0
thread 'import_ecc_scalars' panicked at tests/gpg-agent.rs:650:35:
called `Result::unwrap()` on an `Err` value: Operation failed: Checksum error <GPG Agent>
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
---- import stdout ----
RSA2k with password None
RSA2k with password Some(Password(<Encrypted>))
RSA3k with password None
RSA3k with password Some(Password(<Encrypted>))
RSA4k with password None
RSA4k with password Some(Password(<Encrypted>))
Cv25519 with password None
Cv25519 with password Some(Password(<Encrypted>))
P256 with password None
thread 'import' panicked at tests/gpg-agent.rs:527:43:
called `Result::unwrap()` on an `Err` value: Operation failed: Checksum error <GPG Agent>