fix(sender): write on closed pipe err

[tarrencev]

Handle io.ErrClosedPipe more gracefully.

We should simplify how we are closing senders. It should be triggered by the p.pc.RemoveTrack call, rather than the other way around.

[codecov]

Codecov Report

Merging #176 into master will increase coverage by 0.22%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master     #176      +/-   ##
==========================================
+ Coverage   71.83%   72.05%   +0.22%     
==========================================
  Files           8        8              
  Lines         845      841       -4     
==========================================
- Hits          607      606       -1     
+ Misses        200      197       -3     
  Partials       38       38              

Impacted Files	Coverage Δ
pkg/receiver.go	53.58% <ø> (+0.06%)	⬆️
pkg/sender.go	89.81% <66.66%> (+0.92%)	⬆️

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[OrlandoCo]

We should simplify how we are closing senders. It should be triggered by the p.pc.RemoveTrack call, rather than the other way around.

According to this comit from Pion/Webrtc we should close the sender when a io.EOF it's recieved from the webrtc.Track#Read(), Currently now we are closing senders only on peer disconnecting /failing