fix(webpack-preprocessor): fix webpack preprocessor potential race condition

[kuceb]

fixes potential race condition causing tests to flake

Changelog

Bug Fix: [webpack-preprocessor] fix race condition causing file changes to occasionally not register

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[flotwig]

hmm, doesn't this mean that preprocessor()(file) is resolving 1 tick too early? isn't the fix in the code itself?

[cypress]

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Test summary

8614 • 0 • 124 • 3 • 2

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Run details

Project	cypress
Status	Passed
Commit	a3f1591
Started	Oct 27, 2020 2:30 PM
Ended	Oct 27, 2020 2:42 PM
Duration	12:11 💡
OS	Linux Debian - 10.2
Browser	Multiple

View run in Cypress Dashboard ➡️

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Flakiness

	commands/net_stubbing_spec.ts		1
1	network stubbing > stubbing with static responses > still works after a cy.visit
	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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[kuceb]

@flotwig very observant

[chrisbreiding]

Looks good. Should this be changed to a fix so it releases a new version, since it's fixing the potential race condition in the preprocessor itself?