test: move some gc tests back to parallel/, unmark flaky

These should no longer be flaky after the libuv update.

Refs: #23336

PR-URL: #23356
Reviewed-By: Gus Caplan <[email protected]>
Reviewed-By: Ruben Bridgewater <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Rich Trott <[email protected]>
Reviewed-By: Sakthipriyan Vairamani <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: James M Snell <[email protected]>

Author: addaleax

Diff for: test/sequential/test-gc-http-client-connaborted.js renamed to test/parallel/test-gc-http-client-connaborted.js

@@ -5,19 +5,8 @@ prefix sequential
 # sample-test                       : PASS,FLAKY
 
 [true] # This section applies to all platforms
-# This test will be flaky until https://github.com/libuv/libuv/pull/1742 lands
-# on Node.js.
-test-fs-readfile-tostring-fail: PASS, FLAKY
-# https://github.com/nodejs/node/issues/23066
-test-gc-http-client-timeout: PASS, FLAKY
 # https://github.com/nodejs/node/issues/22336
 test-gc-http-client: PASS,FLAKY
-# https://github.com/nodejs/node/issues/23067
-test-gc-net-timeout: PASS,FLAKY
-# https://github.com/nodejs/node/issues/23089
-test-gc-http-client-onerror: PASS,FLAKY
-# https://github.com/nodejs/node/issues/23219
-test-gc-http-client-connaborted: PASS,FLAKY
 
 [$system==win32]
 # https://github.com/nodejs/node/issues/22327