More relevant duration

[Qwertyn]

If end_time calculate a little earlier, the duration would be more relevant.

# lib/net/ping/external.rb
...
Open3.popen3(*pcmd) do |stdin, stdout, stderr, thread|
  stdin.close
  @end_time = Time.now # <-------
  err = stderr.gets # Can't chomp yet, might be nil
...
# There is no duration if the ping failed
@duration = @end_time - start_time if bool
...

What it can be fraught with?
(What negative consequences can be?)

[chernesk]

I'm looking into this. Thank you for the submission.

[chernesk]

Sorry that this has taken so long to respond to. I have tried a number of scenarios with your suggestion and they all seem to work correctly.

Merged.