Revert "test: mark test-http-regr-gh-2928 as flaky"

This reverts commit 48fcb20.

Refs: 18e00a577d74
PR-URL: #49708
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>

test/sequential/sequential.status

@@ -15,10 +15,6 @@ test-watch-mode-inspect: PASS, FLAKY
 # https://github.com/nodejs/node/issues/47116
 test-http-max-sockets: PASS, FLAKY
 
-[$system==win32 || $system==freebsd]
-# https://github.com/nodejs/node/issues/49564
-test-http-regr-gh-2928: PASS, FLAKY
-
 [$system==linux]
 
 [$system==macos]