Suppress bitrate information if zero

Description

This is a simple clean-up for one issue:

• VBR music appears to return a bitrate of 0. "Bitrate: 0/s ⋅ Codec: Opus Audio ⋅ Sample Rate: 48000 Hz"
  • If bitrate is zero, omit the bitrate and return "Codec: Opus Audio ⋅ Sample Rate: 48000 Hz"
  • Based on my research VBR is 0; however, 0 does not always mean VBR. Is that correct?

Removed proposed change below:

• ALAC (Apple Lossless Audio Codec) music shows "Bitrate: 1.4 MB/s ⋅ Codec: Apple Lossless Audio Codec ⋅ Sample Rate: 44100 Hz"
  • Displaying Codec twice is redundant. This removes ' Codec' at the end.

Types of changes

• Bug fix (non-breaking change which fixes an issue)

Checklist

• I have read the CONTRIBUTING section of the README document.