Implement testresult parser

Create a script that, given a specific workitem ID (aka buildKey):

• it fetches the testresults tarball
• it reads the XML test files
• It prints data points about whether tests were passing/failing or being flaky
• (Later) it inserts the points to a database

Example workitem ID (buildKey):

qt/qtlanguageserver/19b874f185b768bd902a23e40e9a305998bf28ff/MacOSMacOS_12x86_64AndroidAndroid_ANYx86_64Clangqtci-macos-12-x86_64-102-09b1e8DisableTests_Sccache_UseConfigure/f96bee4fbb6540effbede89dc0816a3fc1bf6bc9/build_1661782709

NOTES

• A test_name consists of test_executable+test_function+test_datatag
• A test_name may re-run up to 5 times in order to combat flakiness. The final run is what sets the test_outcome.
  • Possible test outcomes: pass, fail, crash
• Every single run of a test_name can have a test_result.
  • These are printed listed in the XML file: FAIL,XPASS, PASS,XFAIL,BFAIL,BPASS,BXFAIL,BXPASS,SKIP...
• The number of re-runs should also be recorded.

See suggested schema for storing all that in QTQAINFRA-4563.