test_s_generate_parameters: Consider a DSA error in FIPS.

[junaruga]

This PR fixes the "openssl-master with fips provider" specific failure #785 in CI.

---

DSA kengen is not FIPS-approved. The EVP_PKEY_paramgen in the OpenSSL::PKey.generate_parameters("DSA") raises a DSA error in FIPS by the following commit.
openssl/openssl@49a35f0#diff-605396c063194975af8ce31399d42690ab18186b422fb5012101cc9132660fe1R611-R614

[junaruga]

There is another failure in the test_ed25519_not_approved_on_fips in "openssl-master with fip provider" case in CI. This test failure is not related to this PR.

https://github.com/ruby/openssl/actions/runs/10405700727/job/28817053622?pr=786#step:11:103

 1) Failure: test_ed25519_not_approved_on_fips(OpenSSL::TestPKey): OpenSSL::PKey::PKeyError expected but nothing was raised.
/home/runner/work/openssl/openssl/vendor/bundle/ruby/3.0.0/gems/test-unit-ruby-core-1.0.6/lib/core_assertions.rb:462:in `assert_raise'
/home/runner/work/openssl/openssl/test/openssl/test_pkey.rb:174:in `test_ed25519_not_approved_on_fips'
     171:     MC4CAQAwBQYDK2VwBCIEIEzNCJso/5banbbDRuwRTg9bijGfNaumJNqM9u1PuKb7
     172:     -----END PRIVATE KEY-----
     173:     EOF
  => 174:     assert_raise(OpenSSL::PKey::PKeyError) do
     175:       OpenSSL::PKey.read(priv_pem)
     176:     end
     177:   end

[junaruga]

There is another failure in the test_ed25519_not_approved_on_fips in "openssl-master with fip provider" case in CI. This test failure is not related to this PR.

I filed this issue on #787.

[rhenium]

Merged, thanks!

[junaruga]

Thanks for your review!