feat: structured log adapter

[NewGlad]

Thank you for opening a Pull Request! Before submitting your PR, there are a few things you can do to make sure it goes smoothly:

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Fixes googleapis/google-cloud-python#15414 🦕

[google-cla]

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[conventional-commit-lint-gcf]

🤖 I detect that the PR title and the commit message differ and there's only one commit. To use the PR title for the commit history, you can use Github's automerge feature with squashing, or use automerge label. Good luck human!

-- conventional-commit-lint bot
https://conventionalcommits.org/

[NewGlad]

@daniel-sanche could you help, is there a way to run tests and linter in GitHub actions for my changes?

[NewGlad]

@daniel-sanche
Any chance of getting a review for this PR?

[chalmerlowe]

@NewGlad If you are still interested in this PR, please sign the CLA. See this comment.

I know it has been three years. Sorry.

[chalmerlowe]

LGTM

[chalmerlowe]

Gonna close this for now to allow us to migrate this repo to the google-cloud-python mono-repo.

Will re-open it there and see about finishing it then.