calculating bitrate of transcoded results

[AlexKordic]

Produced multivariant playlist now contains proper bitrate:

#EXTM3U
#EXT-X-VERSION:3
#EXT-X-STREAM-INF:PROGRAM-ID=0,BANDWIDTH=2188957288,RESOLUTION=1280x720,NAME="0-720p",FRAME-RATE=30.000
rendition-0/rendition.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=0,BANDWIDTH=745890531,RESOLUTION=640x360,NAME="1-360p",FRAME-RATE=30.000
rendition-1/rendition.m3u8
#EXT-X-STREAM-INF:PROGRAM-ID=0,BANDWIDTH=3884863845,RESOLUTION=2048x858,NAME="2-source"
rendition-2/rendition.m3u8

[codecov]

Codecov Report

Merging #135 (208b914) into main (fe520dd) will increase coverage by 0.66821%.
The diff coverage is 100.00000%.

@@                 Coverage Diff                 @@
##                main        #135         +/-   ##
===================================================
+ Coverage   42.07617%   42.74438%   +0.66821%     
===================================================
  Files             26          26                 
  Lines           1628        1647         +19     
===================================================
+ Hits             685         704         +19     
  Misses           862         862                 
  Partials          81          81                 

Impacted Files	Coverage Δ
transcode/manifest.go	74.19355% <100.00000%> (+0.28051%)	⬆️
transcode/transcode.go	66.85393% <100.00000%> (+3.72893%)	⬆️

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Impacted Files	Coverage Δ
transcode/manifest.go	74.19355% <100.00000%> (+0.28051%)	⬆️
transcode/transcode.go	66.85393% <100.00000%> (+3.72893%)	⬆️

[red-0ne]

LGTM, Thanks Alex