[RTA/DPA BW tests]: Minor maintenance - address #18

Goes with lhcb/Moore!4248 (merged) and lhcb-core/LHCbPR2HD!304 (merged)

Minor maintenance - closes #18 (closed).

TODO:

• Catch anything else minor from other issues?
• Test locally
• Handler MR to start monitoring the error code from make_bandwidth_test_page.