feat: Add support for custom backoff

[camflan]

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Fixes #452 🦕

[generated-files-bot]

Warning: This pull request is touching the following templated files:

• README.md - README.md is managed by synthtool. However, a partials file can be used to update the README, e.g.: https://github.com/googleapis/nodejs-storage/blob/main/.readme-partials.yaml

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[ddelgrosso1]

Hi @camflan thank you for the PR. Can you update the commit message to follow conventional commits.

[camflan]

Hi @camflan thank you for the PR. Can you update the commit message to follow conventional commits.

done! sorry for the delay

[camflan]

@ddelgrosso1 I think this is ready to run CI workflows

[camflan]

@ddelgrosso1 Ready to go

[ddelgrosso1]

Thanks @camflan, apologies on the delay. Will get this merged today. Can you run npm run fix to fix the linter issues?

[camflan]

Thanks @camflan, apologies on the delay. Will get this merged today. Can you run npm run fix to fix the linter issues?

Awesome, thanks! Pushed fix for formatting just now

[ddelgrosso1]

Thanks again for the contribution @camflan!