fix: pool.destroy to clean up async resources

[AriPerkkio]

This issue came up while looking into vitest-dev/vitest#5544.

Tinypool's async resources show up in Vitest's hanging-process reporter.

tinypool/src/EventEmitterAsyncResource.ts

Line 24 in f86e829

class EventEmitterReferencingAsyncResource extends AsyncResource {

 RUN  v1.5.0 /Users/x/vitest/test/cli/fixtures/project

 ✓ |space_1| base.test.ts  (1 test) 2ms

 Test Files  1 passed (1)
      Tests  1 passed (1)
   Start at  21:40:23
   Duration  197ms (transform 17ms, setup 0ms, collect 12ms, tests 2ms, environment 0ms, prepare 66ms)

There are 12 handle(s) keeping the process running

# Tinypool
node:internal/async_hooks:202                                                                             
node:internal/async_hooks:505                                                                             
file:///Users/x/vitest/node_modules/.pnpm/tinypool@0.8.3/node_modules/tinypool/dist/esm/index.js:37 
file:///Users/x/vitest/node_modules/.pnpm/tinypool@0.8.3/node_modules/tinypool/dist/esm/index.js:58 
file:///Users/x/vitest/node_modules/.pnpm/tinypool@0.8.3/node_modules/tinypool/dist/esm/index.js:945
file:///Users/x/vitest/packages/vitest/dist/vendor/cac.dwzv-pfu.js:8776                             
file:///Users/x/vitest/packages/vitest/dist/vendor/cac.dwzv-pfu.js:9425                             
file:///Users/x/vitest/packages/vitest/dist/vendor/cac.dwzv-pfu.js:9450                             

# FILEHANDLE
node:internal/async_hooks:202

... more FILEHANDLES here

# FILEHANDLE
node:internal/async_hooks:202
close timed out after 10000ms
Tests closed successfully but something prevents 2 Vite servers from exiting
You can try to identify the cause by enabling "hanging-process" reporter. See https://vitest.dev/config/#reporters

After this changes the resource is cleaned up during pool.destroy() and it doesn't show up in reports anymore:

 RUN  v1.5.0 /Users/x/vitest/test/cli/fixtures/project

 ✓ |space_1| base.test.ts  (1 test) 1ms

 Test Files  1 passed (1)
      Tests  1 passed (1)
   Start at  21:41:19
   Duration  188ms (transform 12ms, setup 0ms, collect 8ms, tests 1ms, environment 0ms, prepare 53ms)

There are 11 handle(s) keeping the process running

# FILEHANDLE
node:internal/async_hooks:202

... more FILEHANDLES here

# FILEHANDLE
node:internal/async_hooks:202
close timed out after 10000ms
Tests closed successfully but something prevents 2 Vite servers from exiting
You can try to identify the cause by enabling "hanging-process" reporter. See https://vitest.dev/config/#reporters

[AriPerkkio]

Need to do some more manual testing with Vitest but otherwise this should be good.

[AriPerkkio]

Tested with Vitest with all built-in pools and it works fine. I'm not that familiar with Node's async_hooks though - @Aslemammad any thoughts about this PR?

[Aslemammad]

LGTM!