[explorer/memory] Fix conversion of large numbers (>= 2GiB)

At least mawk uses scientific notation when using print for
numbers >=2^31 (INT_MAX of a signed 32-bit int).

`printf "%.f\n"` works around this.
3 jobs for fix/explorer/memory/gt-2g in 2 minutes and 28 seconds (queued for 1 second)
Status Job ID Name Coverage
  Test
passed #10589
pycodestyle

00:00:42

passed #10588
shellcheck

00:00:52

passed #10590
unit_tests

00:00:53