Update example for TEST_DATABASE_URL in CI workflow

- Modified the error message in the build workflow to clarify the expected format for the TEST_DATABASE_URL, specifying the use of a real IP address instead of the placeholder "host".
- This change enhances the guidance provided to users, ensuring correct configuration for database connections in testing scenarios.

.gitea/workflows/build.yml

@@ -36,7 +36,7 @@ jobs:
           set -e
           if [ -z "$TEST_DATABASE_URL" ]; then
             echo "::error::Define el secret TEST_DATABASE_URL en el repo (Gitea → Ajustes → Secretos)."
-            echo "Ejemplo: postgresql://usuario:clave@host:5432/nombre_bd"
+            echo "Ejemplo: postgresql://usuario:clave@127.0.0.1:5432/nombre_bd (host real, no el texto \"host\")"
             exit 1
           fi
           python3 --version