[fix][elixir] missing type mapping for AnyType (#22081)

* fix: unmapped anytype

* add tests for any type in elixir client

---------

Co-authored-by: Enrique Fernandez <[email protected]>

Author: wing328

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

@@ -226,6 +226,7 @@ public ElixirClientCodegen() {
         typeMapping.put("date", "Date.t");
         typeMapping.put("date-time", "DateTime.t");
         // other
+        typeMapping.put("AnyType", "any()");
         typeMapping.put("ByteArray", "binary()");
         typeMapping.put("DateTime", "DateTime.t");
         typeMapping.put("UUID", "String.t");

modules/openapi-generator/src/test/resources/3_0/elixir/petstore-with-fake-endpoints-models-for-testing.yaml

@@ -2134,6 +2134,7 @@ components:
       properties:
         "@type":
           type: string
+        any_type_property: {}
     SingleRefType:
       type: string
       title: SingleRefType

samples/client/petstore/elixir/lib/openapi_petstore/model/any.ex

@@ -8,11 +8,13 @@ defmodule OpenapiPetstore.Model.Any do
 
   @derive JSON.Encoder
   defstruct [
-    :"@type"
+    :"@type",
+    :any_type_property
   ]
 
   @type t :: %__MODULE__{
-    :"@type" => String.t | nil
+    :"@type" => String.t | nil,
+    :any_type_property => any() | nil
   }
 
   def decode(value) do