topdown/units_parse: Avoid extra decimal places for integers. (#5011)

This commit cleans up the output of `units.parse` for integer values. Previously, all values from `units.parse` had their precision set to 10 places past the decimal point, regardless of whether that much precision was actually needed. This commit removes the extra decimal places for integers, giving cleaner outputs.

Signed-off-by: Philip Conrad <philipaconrad@gmail.com>