Fix calculate training time by summing all elapsed times instead the last one#21291

itzhakstern wants to merge 4 commits intoLightning-AI:masterLightning-AI/pytorch-lightning:masterfrom

itzhakstern:bugfix/21257_throughput-monitor-incorrect-training-time-calcitzhakstern/pytorch-lightning:bugfix/21257_throughput-monitor-incorrect-training-time-calcCopy head branch name to clipboard