v4.0.0

• Removed AivenAclAuthorizer and AivenKafkaPrincipalBuilder which are replaced by AivenAclAuthorizerV2 and AivenKafkaPrincipalBuilderV2 respectively. The deleted classes are not Kafka 3+ compatible, their replacements are Kafka 2.4+ compatible. The V2 suffix is kept despite the major version bump, to ensure that code that still references the old classes fails with a class not found error.