migrate from sqlite3 file to psql

main.go

@@ -17,10 +17,10 @@ func main() {
 	_ = godotenv.Load()
 
 	token := mustEnv("DISCORD_TOKEN")
-	dbPath := getEnv("DB_PATH", "cycling_bot.db")
+	dbURL := mustEnv("DATABASE_URL")
 	guildID := getEnv("GUILD_ID", "") // empty = global commands (takes ~1h to propagate)
 
-	database, err := db.Open(dbPath)
+	database, err := db.Open(dbURL)
 	if err != nil {
 		log.Fatalf("open database: %v", err)
 	}