[BUG][Rust] Serde tag of enum has different identifier than specified in spec

[NickUfer]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• What's the actual output vs expected output?
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Description

The rust generator contains this piece of code

openapi-generator/modules/openapi-generator/src/main/java/org/openapitools/codegen/languages/RustClientCodegen.java

Lines 243 to 246 in cb20e74

	// TODO: figure out how to properly have the original property type that didn't go through toVarName
	String vendorExtensionTagName = cm.discriminator.getPropertyName().replace("_", "");
	cm.vendorExtensions.put("x-tag-name", vendorExtensionTagName);
	cm.vendorExtensions.put("x-mapped-models", discriminatorVars);

The replace("_", "") alters the name of the tag which is used to figure out the type of enums and makes it incompatible with the api which implements the openapi spec.

Here an example output of the API

{
  "type": "input",
  "group": "default",
  "attributes": {
    "name": "identifier",
    "type": "text",
    "value": "",
    "required": true,
    "disabled": false,
    "node_type": "input"
  },
  "messages": [],
  "meta": {
    "label": {
      "id": 1070004,
      "text": "ID",
      "type": "info"
    }
  }
}

Here is what the generator generates

#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
#[serde(tag = "nodetype")] 
pub enum UiNodeAttributes {
    #[serde(rename="a")]
    UiNodeAnchorAttributes {
        /// The link's href (destination) URL.  format: uri
        #[serde(rename = "href")]
        // true, false, , String, false
        href: String,
        /// A unique identifier
        #[serde(rename = "id")]
        // true, false, , String, false
        id: String,
        #[serde(rename = "title")]
        // true, false, , crate::models::UiText, true
        title: Box<crate::models::UiText>,
    },
    #[serde(rename="img")]
    UiNodeImageAttributes {
        /// Height of the image
        #[serde(rename = "height")]
        // true, false, , i64, false
        height: i64,
    // ...

In the second line, #[serde(tag = "nodetype")] is wrong, it should be #[serde(tag = "node_type")], but it isn't because of the replacement.

Here is where mustache inserts the wrong value

openapi-generator/modules/openapi-generator/src/main/resources/rust/model.mustache

Line 44 in cb20e74

#[serde(tag = "{{{vendorExtensions.x-tag-name}}}")]

openapi-generator version

6.3.0

OpenAPI declaration file content or url

https://github.com/ory/sdk/blob/master/spec/kratos/v0.11.1.json

Generation Details

packageName: ${RUST_PACKAGE_NAME}
packageVersion: $VERSION
library: reqwest
supportAsync: true
enumNameSuffix: Enum

Steps to reproduce

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