Metric values should be properly formatted

:~$ sonmcli worker metrics
metrics:
  cpu_utilization: 77.88697787944405
  disk_free: 1.93787846656e+11
  disk_total: 2.31197970432e+11
  gpu0_fan: 91
  gpu0_power: 153
  gpu0_temp: 84
  gpu1_fan: 59
  gpu1_power: 126
  gpu1_temp: 82
  ram_free: 1.3919563776e+10
  ram_total: 1.6747761664e+10