Fixed failing tests after performing a merge.
Merge branch '8578_Implement_database_changes'
Re #8578 - Edited conftest- tests from private_key_repository_test use unique database
Re #8578 - Repaired test after review- edited conftest - inicialization database before each test
Re #8578 - Extended tests after review- added second tree of certificates to better cover
Re #8578 - Cover private_key_repository tests- created tests for functions create, read, read_all, update, delete- (+) edited certificate_repository to the same stylistics
Re #8578 - Remaked tests files- created tests for new functions - set_certificate_revoked, clear_certificate_revocation, get_all_revoked_by, get_all_issued_by
Re #8579 - Changed conftest.py of service and DAO tests in such way that test_configuration is now used
Re #8569 Fixed broken tests after injection implementation
Re #8476 - Changed structure of tests- Renamed DAO integration tests so that they are found by pytest- Moved RestAPI tests from UnitTests to IntegrationTests
Re #8472 - Improved SQL connection/cursor fixtures in such way that connection to DB happens only once per test module