[llvm-branch-commits] [CI] Remove Duplicate Heartbeat in Metrics Script (PR #127275)

[Aiden Grossman via llvm-branch-commits]

https://github.com/boomanaiden154 created https://github.com/llvm/llvm-project/pull/127275

This patch removes an extra heartbeat metric in the metrics python file. Before
it was performed twice, once in the main function, and once in the
get_sampled_workflow_metrics function. We only need one to keep everything
happy, and I've chosen to keep the one in get_sampled_workflow_metrics as it
seems a more appropriate place to keep it.