Report total managed memory in GiB and raw bytes

[thbkrkr]

• Reports the total managed memory in GiB (1024³ bytes) instead of GB (1000³ bytes) and in raw bytes to avoid confusion, in the elastic-licensing ConfigMap.

Before:

{
  ...
  "total_managed_memory": "68.72GB"
}

After:

{
   ...
  "total_managed_memory_bytes": "68719476736",
  "total_managed_memory": "64.00GiB"
}

• The calculation of ERUs is also updated to use GiB instead of GB.

Resolves #5465.

[pebrc]

LGTM!