This commit introduces pure pytest logging into a file
Previously, test.py used pytest as a script(not a framework) and just captured pytest stdout and logged this data by itself
This commit sets up the log files format that additionaly display Python processName, threadName adn taskName because test.py test cases use them, and now it is so hard to investigate issues that are connected with parallelism inside test case themselve
In addition, commit splits the logging of different pytest workers(xdist) into different files. If pytest workers have ho failed test - log file for these workers will be deleted
There is also additional logging for failures that will contain a separate file per test failure and contain the error itself (stacktrace) and all capture logs from stdout, stderr during the test run. With --save-log-on-success it will be a separate file per test on pass as well
All this new functionality works with the new xdit scheduler (--test-py-init=True)
Fixes SCYLLADB-713
Closesscylladb/scylladb#28705