fix: make "project-id" parameter optional during initialization

[Amnah199]

Related Issues

• fixes bug: google-vertex-ai forces you to specify the project_id as a parameter #1130

Proposed Changes:

The project is automatically set during authentication using Google Cloud ADCs, which is required for configuration. Therefore, we can make the project-id optional in the component init.

How did you test it?

• Ran existing tests
• Manual testing using examples

Notes for the reviewer

Checklist

• I have read the contributors guidelines and the code of conduct
• I have updated the related issue with new insights and changes
• I added unit tests and updated the docstrings
• I've used one of the conventional commit types for my PR title: fix:, feat:, build:, chore:, ci:, docs:, style:, refactor:, perf:, test:.

[julian-risch]

Looks quite good to me! I suggest that we remove the project_id param from the initialization of the VertexAIGeminiChatGenerator too. Other than that ready to be merged.

I checked what error message we get if no project id is provided at all.

    raise GoogleAuthError(project_not_found_exception_str) from exc
google.auth.exceptions.GoogleAuthError: Unable to find your project. Please provide a project ID by:
- Passing a constructor argument
- Using vertexai.init()
- Setting project using 'gcloud config set project my-project'
- Setting a GCP environment variable
- To create a Google Cloud project, please follow guidance at https://developers.google.com/workspace/guides/create-project

Looks good.

[julian-risch]

One more change request: let's remove project_id from the test_to_dict and test_from_dict. We can keep it in test_to_dict_with_params and test_from_dict_with_param.

[Amnah199]

VertexAIGeminiChatGenerator is already updated. I'll update the tests too 👍

[Amnah199]

@julian-risch updated the examples and also removed project_id from all tests except init. Let me know WDYT.

[julian-risch]

LGTM! 👍