Use 'tester' directory in sources as default resource directory
This is the first step of a migration which aims to make flexisip_tester to be invoked without installation. Right now, some test suites can be run after installation whereas others can be run with or without installation. Thus, the CI execute flexisip_tester after installation by using --resource-dir option.
When all the test suites will be able to be run without installation, the CI will be set to execute all the tests without installation.
Edited by François Grisez