sql: deprecate client
sql: deprecate client

This client was accidentally generated under the wrong package. The
correct package is "sqladmin". This client will be removed in a
future release.

Change-Id: Ia9495074ff2cbb933e02b871afd441a285db3761
Reviewed-on: https://code-review.googlesource.com/c/google-api-go-client/+/54410
Reviewed-by: Tyler Bui-Palsulich <b41e4aa57d2ad7eb1b29835a1b483e209dcc3c0e@google.com>

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