clean code

[MoonBall]

Clean code since key is ensured to be true.

swr/src/use-swr.ts

Lines 63 to 67 in f787624

	if (!key) return Promise.resolve()
	const updaters = CACHE_REVALIDATORS[key]
	if (key && updaters) {

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Sandbox	Source
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SWR-States	Configuration
SWR-Infinite	Configuration
SWR-SSR	Configuration