fix(test): close all open connections in abstract_client test (#1917)

* fix: tets hang up

* fix(test): close open connections

* test: catch error

* feat: move clean_method class to help

* fix: hang tests

* fix: lint style

* fix: teardown helper functionality

* docs: change examples according new changes

* fix(test): close all open connections in abstract_client test

* fix(lint): rename variable

* fix(test): prevent hanging of some tests

* test: let the responsibility to beforeEachExec method of closing the open connections

* lint: fix style

* fix(test): do not listen connect event

* Revert "fix(test): do not listen connect event"

This reverts commit 2dc39f2.

* fix(test): do not for close client connection

* fix(test): hanging by clock

* test: remove unnecesary timeout

* fix(typo): rename variable

---------

Co-authored-by: Daniel Lando <[email protected]>