Add BigQuery Remote Vision Function code sample

[autoerr]

Description

First sample for #8425

Checklist

• [x] Before submitting a pull request, please open an issue for discussion if you are not associated with Google.
• [x] I have followed Sample Guidelines from AUTHORING_GUIDE.MD
• [x] README is updated to include all relevant information
• [x] Tests pass: nox -s py-3.9 (see Test Environment Setup)
• [x] Lint pass: nox -s lint (see Test Environment Setup)
• [ ] These samples need a new API enabled in testing projects to pass (let us know which ones)
• [ ] These samples need a new/updated env vars in testing projects set to pass (let us know which ones)
• [x] Please merge this PR for me once it is approved.
• [ ] This sample adds a new sample directory, and I updated the CODEOWNERS file with the codeowners for this sample

[snippet-bot[bot]]

Here is the summary of changes.

You are about to add 1 region tag.

• bigquery/remote-function/vision/vision_function.py:15, tag bigquery_remote_function_vision

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