for issue #389

after updating to azure-keyvault v1.0.0, the project breaks. The PR fixes it.

However, it will also break user's existing programs that use AKV. We will need to document this breaking change:

Previous, in order to construct SQLServerColumnEncryptionAzureKeyVaultProvider object, client code needs to construct a SQLServerKeyVaultAuthenticationCallback object first by implementing SQLServerKeyVaultAuthenticationCallback interface (with clientID and clientKey) and also provide an ExecutorService object. By doing so, user needs to handle SQLServerKeyVaultAuthenticationCallback interface and take care of the ExecutorService object (e.g. shutdown) by themselves.

Now, with the latest version of AKV, user can create SQLServerColumnEncryptionAzureKeyVaultProvider object directly with clientID and clientKey. Without implementing interface or providing ExecutorService, it reduces complexity on user side.

SQLServerColumnEncryptionAzureKeyVaultProvider akvProvider = new SQLServerColumnEncryptionAzureKeyVaultProvider(clientID, clientKey);