feat: Implement CogVideo model

[mrsbeep]

Description

Add CogVideo model. Currently, to test this model, we need a server that runs this model and provides an endpoint.
Note: This is the drafe PR. I would like to receive more reviews to complete this.

Motivation and Context

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• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds core functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
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• Example (update in the folder of example)

Implemented Tasks

• Implement CogVideo model

Checklist

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• My change requires a change to the documentation.
• I have updated the tests accordingly. (required for a bug fix or a new feature)
• I have updated the documentation accordingly.

[koch3092]

It seems that COGVIDEO_API_BASE_URL in env can never be read

[koch3092]

Thanks @mrsbeep , there is a question for discussion