prompts.get_version doesn't provide the prompt_data of the particular version

The **_prompts.get_version_** function is intended to retrieve the content of a specific versioned prompt, but currently returns the latest prompt data instead — indicating a bug in its implementation.

#### Environment details
- Python version: >= 3.11
- `google-cloud-aiplatform` version: - v1.119.0 and v1.120.0

#### Steps to reproduce

1. Create multiple versions of prompts using **_prompts.create_version_**
2. Fetch the particular version of prompt using **_prompts.get_version_**

#### Code example

#### Output