database/sql: TestConversions add forgotten fields wantbytes and wantraw

database/sql: TestConversions add forgotten fields wantbytes and wantraw

The fields wantbytes and wantraw in the test struct `conversionTest` has
been forgotten to include in the TestConversions function.

Change-Id: I6dab69e76de3799a1bbf9fa09a15607e55172114
Reviewed-on: https://go-review.googlesource.com/66610
Reviewed-by: David Crawshaw <crawshaw@golang.org>
Reviewed-by: Daniel Theophanes <kardianos@gmail.com>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>