Add audit 4 to readme

[amiecorso]

No description provided.

[codecov]

Codecov Report

Merging #711 (09599fe) into master (cb5cb42) will not change coverage.
The diff coverage is n/a.

❗ Current head 09599fe differs from pull request most recent head a9b3be4. Consider uploading reports for the commit a9b3be4 to get more accurate results

@@          Coverage Diff           @@
##           master    #711   +/-   ##
======================================
  Coverage    54.7%   54.7%           
======================================
  Files          14      14           
  Lines         979     979           
  Branches      152     152           
======================================
  Hits          536     536           
  Misses        386     386           
  Partials       57      57           

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[openzeppelin-code]

Add audit 4 to readme

Generated at commit: a9b3be4bdf67d677b9fc056c4098b9c325ac72cd

🚨 Vulnerabilities Summary

Process	Issues	Results
Contract Inspector	note low Total	21 9 30
Dependency Checker	Total	0

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For more details view the full report in OpenZeppelin Code