sql: re-deprecate client

Reapplying notice added in CL 54410. It seem like this API
is still receiving updates under the bad package name. Blocking
generation so notice persists.

Change-Id: I2a19322ffa927b22377eb0bcad8d18d5ae452195
Reviewed-on: https://code-review.googlesource.com/c/google-api-go-client/+/55770
Reviewed-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Tyler Bui-Palsulich <tbp@google.com>

google-api-go-generator/gen.go

diff --git a/google-api-go-generator/gen.go b/google-api-go-generator/gen.go
index 8278efa..d8a41dd 100644
--- a/google-api-go-generator/gen.go
+++ b/google-api-go-generator/gen.go
@@ -125,6 +125,7 @@
 // skipAPIGeneration is a set of APIs to not generate when generating all clients.
 var skipAPIGeneration = map[string]bool{
 	"customsearch:v1": true,
+	"sql:v1beta4":     true,
 }
 
 func main() {

sql/v1beta4/sql-gen.go

diff --git a/sql/v1beta4/sql-gen.go b/sql/v1beta4/sql-gen.go
index ab97f21..efb968a 100644
--- a/sql/v1beta4/sql-gen.go
+++ b/sql/v1beta4/sql-gen.go
@@ -39,6 +39,10 @@
 //   sqlService, err := sql.NewService(ctx, option.WithTokenSource(config.TokenSource(ctx, token)))
 //
 // See https://godoc.org/google.golang.org/api/option/ for details on options.
+//
+// Deprecated: please use "google.golang.org/api/sqladmin/v1beta4" instead. This
+// client was accidentally generated under the wrong package. The correct package
+// is "sqladmin". This client will be removed in a future release.
 package sql // import "google.golang.org/api/sql/v1beta4"
 
 import (