fix: typo

config/config.exs

@@ -138,7 +138,7 @@ config :mobilizon, Mobilizon.Web.Email.Mailer,
   username: System.get_env("MOBILIZON_SMTP_USERNAME", nil),
   password: System.get_env("MOBILIZON_SMTP_PASSWORD", nil),
   no_mx_lookups: System.get_env("MOBILIZON_SMTP_NO_MX_LOOKUP", false),
-  auth: System.get_env("MOBILIZON_SMTP_AUTH", "if_available")
+  auth: System.get_env("MOBILIZON_SMTP_AUTH", "if_available"),
   tls: System.get_env("MOBILIZON_SMTP_TLS", "if_available"),
   tls_options:
     :tls_certificate_check.options(System.get_env("MOBILIZON_SMTP_SERVER", "localhost")),