feat: migrate fetch captcha config to use db_*

build.rs

@@ -14,7 +14,6 @@
  * You should have received a copy of the GNU Affero General Public License
  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
  */
-use std::env;
 use std::process::Command;
 
 use sqlx::types::time::OffsetDateTime;