[jest] Add useFakeTimers implementation argument

[mskelton]

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[typescript-bot]

@mskelton Thank you for submitting this PR! I see this is your first time submitting to DefinitelyTyped 👋 - keep an eye on this comment as I'll be updating it with information as things progress.

Code Reviews

Because this is a widely-used package, a DT maintainer will need to review it before it can be merged.

Status

• ✅ No merge conflicts
• ✅ Continuous integration tests have passed
• ❌ Most recent commit is approved by DT maintainers

Once every item on this list is checked, I'll ask you for permission to merge and publish the changes.

---

Diagnostic Information: What the bot saw about this PR

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[typescript-bot]

🔔 @NoHomey @jwbay @asvetliakov @alexjoverm @epicallan @ikatyang @wsmd @JamieMason @douglasduteil @ahnpnl @JoshuaKGoldberg @UselessPickles @r3nya @Hotell @sebald @andys8 @antoinebrault @favna @gstamac @ExE-Boss @quassnoi @Belco90 @tonyhallett @ycmjason @devanshj @pawfa @regevbr - please review this PR in the next few days. Be sure to explicitly select Approve or Request Changes in the GitHub UI so I know what's going on.

[typescript-bot]

👋 Hi there! I’ve run some quick measurements against master and your PR. These metrics should help the humans reviewing this PR gauge whether it might negatively affect compile times or editor responsiveness for users who install these typings.

Let’s review the numbers, shall we?

Comparison details 📊

	master	#45234	diff
Batch compilation
Memory usage (MiB)	83.2	83.8	+0.6%
Type count	14713	14719	0%
Assignability cache size	35944	35945	0%
Language service
Samples taken	2557	2563	0%
Identifiers in tests	2557	2563	0%
getCompletionsAtPosition
Mean duration (ms)	324.4	336.0	+3.6%
Mean CV	10.0%	9.0%
Worst duration (ms)	440.4	449.8	+2.1%
Worst identifier	toThrowErrorMatchingInlineSnapshot	toBeLessThanOrEqual
getQuickInfoAtPosition
Mean duration (ms)	320.7	332.3	+3.6%
Mean CV	10.1%	9.1%	-10.2%
Worst duration (ms)	419.8	442.0	+5.3%
Worst identifier	MockedTestClass_testClassMethod_0_ret	test

It looks like nothing changed too much. I won’t post performance data again unless it gets worse.

[orta]

Thanks!

[typescript-bot]

I just published @types/jest@26.0.0 to npm.