Enable dynamic complex property without @odata.type

Assemblies affected
Which assemblies and versions are known to be affected e.g. ASP.NET Core OData 8.x

Reproduce steps

Consider the following json request payload, the type of 'condition' is an open type, and it accepts dynamic properties.

where, StringEqualsIgnoreCase is dynamic complex type property

{
   "condition": {
         "StringEqualsIgnoreCase": {
               "awsTag":[
                         "finance",
                          "hr",
                         "legal"
                    ]
                },
                "key1": "value1",
                 "key2": [
                   "value2",
                   "value3"
                ],
                "key3": "value4"
       }
}

The above payload can't pass deserialization because there's no type for
a) StringEqualsIgnoreCase
b) awsTag
C) key2

We have to let customer provide types as below, then it can work.

{
  "condition": {
    "StringEqualsIgnoreCase": {
        "@odata.type":"microsoft.graph.awsCondition",
        "awsTag@odata.type":"Collection(Edm.String)",
        "awsTag":[
            "finance",
            "hr",
            "legal"
        ]
      },
      "key1": "value1",
      "key2@odata.type": "Collection(Edm.String)",
      "key2": [
          "value2",
          "value3"
      ],
      "key3": "value4"
    }
}

Expected behavior
Actually, we don't need customers to provide the types since they are dynamic properties.

Additional context
We can deserialize 'StringEqualsIgnoreCase' as an instance of 'ODataObject', where 'ODataObject' can be defined as:

public class ODataObject: Dictionary<string, object>
{}