Update mailjet_resources.go TemplateID type

[gundersen-f]

Change InfoMessagesV31 struct TemplateID from interface{} to int.
{"Messages":[{"Errors":[{"ErrorClass":"","ErrorMessage":"Type mismatch. Expected type \"integer\".","ErrorRelatedTo":["TemplateID"],"StatusCode":400}]}]}

[kevpie]

Thanks for posting this.
I burned an hour or two figuring this out.

The error I was receiving in library was {"Messages":null}

When I used curl I received this

{
 "ErrorIdentifier":".....uuid....",
 "ErrorCode":"mj-0004",
 "StatusCode":400,
 "ErrorMessage":"Type mismatch. Expected type \"int64\".",
 "ErrorRelatedTo":["Messages.TemplateID"]
}