feat: add ping stats

[amishshah]

Please describe the changes this PR makes and why it should be merged:

Resolves #70.

Fixes a bug in VoiceWebSocket where if no heartbeat acknowledge was ever received, then the WebSocket would continually keep heartbeating instead of disconnecting.

Adds tests to VoiceWebSocket and the new feature.

Status and versioning classification:

• Code changes have been tested against the Discord API, or there are no code changes
• This PR changes the library's interface (methods or parameters added)

[codecov[bot]]

Codecov Report

Merging #77 (34e37b4) into main (f140bd4) will increase coverage by 5.00%. The diff coverage is 80.95%.

@@            Coverage Diff             @@
##             main      #77      +/-   ##
==========================================
+ Coverage   44.01%   49.02%   +5.00%     
==========================================
  Files          15       15              
  Lines         602      616      +14     
  Branches      133      135       +2     
==========================================
+ Hits          265      302      +37     
+ Misses        335      312      -23     
  Partials        2        2              

Impacted Files	Coverage Δ
src/VoiceConnection.ts	79.27% <0.00%> (-2.21%)	:arrow_down:
src/networking/Networking.ts	3.93% <ø> (ø)
src/networking/VoiceWebSocket.ts	88.09% <94.44%> (+88.09%)	:arrow_up:

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[amishshah]

Converting this PR back to a draft until tests can be implemented for it.