fix: removed env variable, configured a form field for editing email connect host

client/src/Validation/validation.js

@@ -307,6 +307,7 @@ const advancedSettingsValidation = joi.object({
 	systemEmailPort: joi.number().allow(null, ""),
 	systemEmailAddress: joi.string().allow(""),
 	systemEmailPassword: joi.string().allow(""),
+	systemEmailConnectionHost: joi.string().allow(""),
 	jwtTTLNum: joi.number().messages({
 		"number.base": "JWT TTL is required.",
 	}),