[XML-report] Make XML report testcase items names unique

Current situation

When we run a workflow that contains two generator jobs on the same items, the XML generated will not be correctly read by GitLab if a testsuite has the same name as another one. GitLab will only handle one testsuite with that name.

For example:

Here is the GitLab output for this XML file with 8 tests:

I manually changed the name in the XML file to make it unique, and here is the output:

GitLab seems to use the name of the testsuite to determine which suite to display.

Another study around GitLab indicates that the Suite on the GUI is related to testcase=>className and the name is related to testcase=>name.

Desired outcome

One solution might be to generate a different report for each generator job.