* test_sign_verify
  I created the signature text (`signature_encoded.txt`), that is used as a
  text to create the `signature0` in the `test_sign_verify` by the following
  steps with the `openssl` CLI on FIPS module.
  ```
  $ OPENSSL_DIR="${HOME}/.local/openssl-3.4.0-dev-fips-debug-3c6e114959"
  $ export OPENSSL_CONF="${OPENSSL_DIR}/ssl/openssl_fips.cnf"

  $ echo -n "Sign me!" > data.txt
  $ "${OPENSSL_DIR}/bin/openssl" dgst -sha256 -sign test/openssl/fixtures/pkey/rsa2048.pem data.txt > signature.txt
  $ cat signature.txt | base64 > signature_encoded.txt
  ```

https://github.com/ruby/openssl/commit/091f3eb421