fix: revert "perf: update tinypool to v2.0.0 (#8513)"

[AriPerkkio]

This reverts commit a8c7f73.

Description

• Closes fix(vitest): rm Node 18 from supported engines #8525

We want to support EOL Node 18 too.

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[RobinTail]

I don't think you should revert it, @AriPerkkio .
Node 18 is EOL and vitest 4 would be the next major release that implies breaking changes.
It is the good moment to drop the support of the outdated software.

[AriPerkkio]

I agree 100%, but we need to support EOL Node 18 in Vitest 4.

[RobinTail]

Then I suggest to add tests against Node 18, @AriPerkkio
That would help to avoid similar issues

Though, it looks like it was removed for a reason:
#8300

[AriPerkkio]

Then I suggest to add tests against Node 18

Yup I agree completely.

[belgattitude]

Worth to bring to your attention

Seems that Tinypool v2 makes it possible to run vitest with latest bun: oven-sh/bun#4145 (comment)

[sheremet-va]

We decided to remove support for node 18.