feat: deprecate cy.route(), remove experimentalNetworkStubbing flag

[flotwig]

TR-493

User facing changelog

• cy.route() and cy.server() have been deprecated and will be moved to a plugin in a future release. Consider using cy.http() instead.
• The experimentalNetworkStubbing flag has been removed and cy.http() is now always available.

Additional details

How has the user experience changed?

After

During cypress open or cypress run is experimentalNetworkStubbing is present:

In Console log during cypress open when using cy.server() or cy.route()

PR Tasks

• Have tests been added/updated?
• Has the original issue or this PR been tagged with a release in ZenHub?
• Has a PR for user-facing changes been opened in cypress-documentation? docs(net-stubbing): deprecate cy.route(), remove experimentalNetworkStubbing cypress-documentation#3323
• Have API changes been updated in the type definitions?
• Have new configuration options been added to the cypress.schema.json?

[cypress-bot]

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[cypress]

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Test summary

8713 • 0 • 118 • 3 • 1

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Run details

Project	cypress
Status	Passed
Commit	af26ac9
Started	Nov 17, 2020 3:37 PM
Ended	Nov 17, 2020 3:50 PM
Duration	12:56 💡
OS	Linux Debian - 10.2
Browser	Multiple

View run in Cypress Dashboard ➡️

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Flakiness

	cypress/integration/retries.ui.spec.js		1
1	runner/cypress retries.ui.spec > opens attempt on each attempt failure for the screenshot, and closes after test passes

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This comment has been generated by cypress-bot as a result of this project's GitHub integration settings. You can manage this integration in this project's settings in the Cypress Dashboard

[jennifer-shehane]

Just a minor suggestion. Looks good otherwise.

I wish we had the display of warnings in the Command Log to make these notices more obvious.

[cypress-bot]

Released in 6.0.0.

This comment thread has been locked. If you are still experiencing this issue after upgrading to
Cypress v6.0.0, please open a new issue.