[RTA DPA BW Tests] Short term fix for buffer failures in `hlt2_and_spruce_bandwidth_test`

Short term fix for #35 (comment 8723098)

Should resolve errors of this kind, and that is harming the evaluation of the Turbo stream.

MDFIOAlg                              FATAL  Standard std::exception is caught 
MDFIOAlg                              ERROR Found too big event (10154864 bytes), not fitting into input buffers. Please consider changing ioalg_buffer_nb_events to at least 204
HLTControlFlowMgr                     FATAL Event failed in Node createODIN/Decode_ODIN
HLTControlFlowMgr                      INFO Application return code set to 3
HLTControlFlowMgr                     FATAL Event 9240 on slot 0 failed!
HLTControlFlowMgr                     FATAL *** Too many consecutive failures 1, stopping now ***

Better handling/ longer term solution is preferred but this is just to get the test correctly functional again.

ToDo

• ci-test with a Moore MR (lhcb/Moore!3478) : lhcb/Moore!3478 (comment 8734718)
• In parallel, review