Add default_time_zone to Spanner database resource (#13762) (#978)

[upstream:b4487f55c5e933b0699f5160bc40faf77546ca39]

Signed-off-by: Modular Magician <[email protected]>

Author: modular-magician

spanner_database_basic/main.tf

@@ -8,6 +8,7 @@ resource "google_spanner_database" "database" {
   instance = google_spanner_instance.main.name
   name     = "my-database-${local.name_suffix}"
   version_retention_period = "3d"
+  default_time_zone = "UTC"
   ddl = [
     "CREATE TABLE t1 (t1 INT64 NOT NULL,) PRIMARY KEY(t1)",
     "CREATE TABLE t2 (t2 INT64 NOT NULL,) PRIMARY KEY(t2)",