docs: document patch-package best practices

[flotwig]

• Closes Document patch-package #20400

User facing changelog

n/a

Additional details

• Documents best practices around using patch-package in the Cypress monorepo.

How has the user experience changed?

PR Tasks

• [na] Have tests been added/updated?
• [na] Has the original issue (or this PR, if no issue exists) been tagged with a release in ZenHub? (user-facing changes only)
• [na] Has a PR for user-facing changes been opened in cypress-documentation?
• [na] Have API changes been updated in the type definitions?
• [na] Have new configuration options been added to the cypress.schema.json?

[cypress-bot]

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[cypress]

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Test summary

19278 • 0 • 218 • 0 • 1

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Run details

Project	cypress
Status	Passed
Commit	938f72a
Started	Mar 9, 2022 4:17 PM
Ended	Mar 9, 2022 4:29 PM
Duration	11:44 💡
OS	Linux Debian - 10.10
Browser	Multiple

View run in Cypress Dashboard ➡️

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Flakiness

	cypress/integration/cypress/proxy-logging_spec.ts		1
1	Proxy Logging > request logging > xhr log has response body/status code

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[jennifer-shehane]

Looks great. Thanks for documenting. @flotwig Can you ping the team in Slack to inform them of the new doc once this is merged?