refactor(config): Load gotenberg url from env

models/config.go

@@ -14,4 +14,5 @@ type Config struct {
 	SponsoringBarcodeFormat  string `mapstructure:"SPONSORING_BARCODEFORMAT"`
 	SponsoringBarcodePrefix  string `mapstructure:"SPONSORING_BARCODEPREFIX"`
 	CertificateFooter        string `mapstructure:"CERTIFICATE_FOOTER"`
+	GotenbergBaseUrl         string `mapstructure:"GOTENBERG_BASEURL"`
 }