1) new test run metrics - requestThroughput and bytesThroughput - calc, save and return to ui 2) new api - delete multiple test suites

Checklist:

[x] I have included a meaningful summary of my PR's content
[x] I have linked my PR to the relevant issue
[x] I have performed a self-review of my code
[x] I have commented my code, particularly in hard-to-understand areas
[x] My changes do not generate new compliance warnings / errors
[x] I have tested that my fix or enhancement is effective or that my feature works
[x] New and existing unit tests pass locally with my changes

att / qujata