[BUG] `ReferenceLinks` model incorrect

The model describes an object with a links key.
https://github.com/microsoft/azure-devops-python-api/blob/451cade4c475482792cbe9e522c1fee32393139e/azure-devops/azure/devops/v5_1/git/models.py#L3040-L3054
All models specify this model as the value of a _links key, eg, GitCommit,
https://github.com/microsoft/azure-devops-python-api/blob/451cade4c475482792cbe9e522c1fee32393139e/azure-devops/azure/devops/v5_1/git/models.py#L3356
However, this doesn't fit actual or sample responses

  "_links": {
    "self": {
      "href": "https://dev.azure.com/fabrikam/_apis/git/repositories/278d5cd2-584d-4b63-824a-2ba458937249/commits/be67f8871a4d2c75f13a51c1d3c30ac0d74d4ef4"
    },
    "repository": {
      "href": "https://dev.azure.com/fabrikam/_apis/git/repositories/278d5cd2-584d-4b63-824a-2ba458937249"
    },
    "changes": {
      "href": "https://dev.azure.com/fabrikam/_apis/git/repositories/278d5cd2-584d-4b63-824a-2ba458937249/commits/be67f8871a4d2c75f13a51c1d3c30ac0d74d4ef4/changes"
    },
    "web": {
      "href": "https://dev.azure.com/fabrikam/_git/Fabrikam-Fiber-Git/commit/be67f8871a4d2c75f13a51c1d3c30ac0d74d4ef4"
    },
    "tree": {
      "href": "https://dev.azure.com/fabrikam/_apis/git/repositories/278d5cd2-584d-4b63-824a-2ba458937249/trees/7fa1a3523ffef51c525ea476bffff7d648b8cb3d"
    }
  }

Consequently, clients deserialize _links to empty object despite actual data.

azure-devops/azure/devops/v5_1/git/models.py の3040-3054行付近にある ReferenceLinks の定義から始め、3356行付近の GitCommit およびリンクされた REST sample と比較します。モデルがレスポンスの _links 構造を表現し、クライアントが値の入った links を空のオブジェクトとしてデシリアライズしなくなれば完了です。