Remove extra newline when pretty printing text serialized from foreing types

[RedIODev]

I currently have the problem that serializing types that serialize to text are not placed inline but on their own line.
Example:

use uuid::Uuid;
#[derive(From, Debug, Serialize, Deserialize)]
pub struct Guid {
    #[serde(rename = "@type")]
    pub id_type: String,
    #[serde(with = "simple_uuid")]
    #[serde(rename = "$text")]
    pub id: Uuid,
}

is serialized to (when the guid field is named "book:id"):

<book:id type="guid">
  3e114c9829ce41728902866e39b4e5c7
</book:id>

The required formatting for the target application is:

<book:id type="guid">3e114c9829ce41728902866e39b4e5c7</book:id>

I haven't found a way to change this behavior.
Great regards
RedIODev

[Mingun]

Duplicate of #729