feat: 增加sendcloud邮件服务器的支持 (#947)

* 增加sendcloud邮件服务器的支持

* 调整代码结构

* Used slince.Contains function

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Co-authored-by: shih <shih@knownsec.com>

common/constants.go

@@ -62,6 +62,10 @@ var EmailDomainWhitelist = []string{
 	"yahoo.com",
 	"foxmail.com",
 }
+var EmailLoginAuthServerList = []string{
+	"smtp.sendcloud.net",
+	"smtp.azurecomm.net",
+}
 
 var DebugEnabled bool
 var MemoryCacheEnabled bool