feat: support SaslHandshakeRequest v0 for SCRAM

[zhaomoran]

Fix #1918 ,Maybe other scram issues are also relevant！Thanks！

[dnwe]

Thanks, the fix looks good to me

[dnwe]

@zhaomoran please can you take a look at the test failures?

2021-08-09T13:35:20.5596060Z --- FAIL: TestSASLSCRAMSHAXXX (0.01s)
2021-08-09T13:35:20.5597111Z --- FAIL: TestSASLSCRAMSHAXXX/SASL/SCRAMSHAXXX_successful_authentication (0.00s)
2021-08-09T13:35:20.5599071Z --- FAIL: TestSASLSCRAMSHAXXX/SASL/SCRAMSHAXXX_SCRAM_client_step_error_client (0.00s)
2021-08-09T13:35:20.5600904Z --- FAIL: TestSASLSCRAMSHAXXX/SASL/SCRAMSHAXXX_server_authentication_error (0.00s)
2021-08-09T13:35:20.5602160Z --- PASS: TestSASLSCRAMSHAXXX/SASL/SCRAMSHAXXX_unsupported_SCRAM_mechanism (0.00s)

[zhaomoran]

@dnwe I'm sorry，I ignored the test! Net.SASL.Version default is SASLHandshakeV0 in config.Newconfig() . This test is for V1；

[bai]

@zhaomoran Looks like CI is still failing. Do you think you could take a look at it?

[dnwe]

It looked like it just needed gofmt -s -w broker.go when I last checked. I'd have pushed up the fix myself, but the branch didn't permit write access to maintainers :)

[Neustradamus]

@zhaomoran: #1944 has been solved or not?
The ticket is always open.

[cypres]

This PR changed the default behavior of conf.Net.SASL.Version to SASLHandshakeV0 instead of SASLHandshakeV1, breaking clients on sarama upgrades.

[dnwe]

@duedal conf.Net.SASL.Version had been defaulted to V0 for a while (if I remember correctly, due to a bug in Azure) — what changed here is that SCRAM had previously only implemented V1 handshaking and this PR added the missing capability and as a side effect conf.Net.SASL.Version is now being adhered to for SCRAM as well.

When you say "breaking clients on sarama upgrades" — can you elaborate? Any Apache Kafka cluster that supports/supported SCRAM using SASLHandshakeV1 should also support it via the legacy SASLHandshakeV0 method?