dlp: remove defunct v2beta1 dir
dlp: remove defunct v2beta1 dir

Change-Id: I377b8ed4b1dbd6ef3d11320a0e19aa1662828681
Reviewed-on: https://code-review.googlesource.com/c/google-api-go-client/+/39052
Reviewed-by: kokoro <2ac7b1f3fa578934c95181d4272be0d3bca00121@google.com>
Reviewed-by: Chris Broadfoot <0c2851a4f8ab4aa5606e69c0757771dd13dbe686@google.com>

googleapis/google-api-go-client,google/google-api-go-client,google/google-api-go-client,googleapis/google-api-go-client