fix: Fix getStreamingNetworkErrorMetadata to support videojs 7

[idsulik]

Description

#1566

Specific Changes proposed

Added property existing checking to avoid exception if you use 7th version of the videojs

Requirements Checklist

• Bug fixed
• Reviewed by Two Core Contributors

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[codecov]

Codecov Report

Attention: Patch coverage is 50.00000% with 1 line in your changes missing coverage. Please review.

Project coverage is 83.99%. Comparing base (1e721c1) to head (d525752).

Files with missing lines	Patch %	Lines
src/error-codes.js	50.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1567      +/-   ##
==========================================
- Coverage   84.00%   83.99%   -0.01%     
==========================================
  Files          44       44              
  Lines       11707    11709       +2     
  Branches     2623     2624       +1     
==========================================
+ Hits         9834     9835       +1     
- Misses       1873     1874       +1     

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[idsulik]

@mister-ben @gkatsev hi! Is there anything I can do to push the changes?)