fix(server-ct): support exclusive inline config

[lmiller1990]

• Closes Component testing does not honour configuration values provided by plugins.  #16424

User facing changelog

Correctly use componentFolder and testFiles values from returned from plugins in component testing runner.

I added a test project, but this does not run on CI. It will once #16354 is merged.

I tested in manually by doing cd packages/server-ct/test/fixtures/projects/inline-config-only and running yarn cy:open. It found the component and spec files correctly.

Additional details

We were the resolved values for testFiles and componentFolder as specified in cypress.json. If you specified different values in the config returned from plugins, they were not used. We should be using the resolved values.

How has the user experience changed?

Allow customizing testFiles and componentFolder by returning a config object in plugins.

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?
• Have API changes been updated in the type definitions?
• Have new configuration options been added to the cypress.schema.json?

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[cypress]

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Test summary

460 • 0 • 6 • 0 • 0

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Run details

Project	cypress
Status	Passed
Commit	8298361
Started	May 12, 2021 6:44 AM
Ended	May 12, 2021 6:53 AM
Duration	09:24 💡
OS	Linux Debian - 10.8
Browser	Electron 89

View run in Cypress Dashboard ➡️

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[agg23]

Aren't we deprecating componentFolder? Seems like we should do that soon, rather than fixing bugs with it

[lmiller1990]

I think we are @agg23, but what will take it's place when when is not clear. Since it could be months before it is deprecated, this fix is worth having - especially considering it's a breaking change (this was working pre 7.0).

testFiles is not going away, that will stick around (was also broken as part of the original issue, another regression).