Add option for NONE attestation protocol

[Jeffery-Wasty]

Similar to what Microsoft.Data.SqlClient added in their 4.1 release, we need to support no attestation in the JDBC driver. This reduces security but allows users to use VBS secure enclaves in environments where attestation services are unavailable. The driver should consume the information from the server about the secure enclave but not use the attestation service to validate it.

To enable this mode, specify enclaveAttestationProtocol=NONE in the connection string.

Files changed:

• New SQLNoneEnclaveProvider.java - New filed added for the NONE protcol option. Based off of SQLAASEnclaveProvider.java with token/URL validation removed.
• SQLServerDriver.java - Added NONE option to protocol options.
• SQLServerConnection.java - Pointed the driver towards SQLNoneEnclaveProvider in the case of NONE attestation option. As well, added checks for protocol type:
  • A missing attestation URL is only a problem if the protocol is not NONE.
  • A protocol of NONE must use secure enclaves.
• EnclavePackageTest.java - Pointed NONE protocol to be tested against VBS enclaves, as well as making sure the protocol cannot be none for tests run in this file (will return a false negative).

This PR also removed a build warning by adding a comment missing from a variable in SQLServerConnection