docs(website): update relay proxy image name

[mbezhanov]

Description

I noticed that the Getting Started documentation was pointing to a non-existent Docker Hub image, so I corrected it.

Checklist

• I have tested this code
• I have added unit test to cover this code
• I have updated the documentation (README.md and /website/docs)
• I have followed the contributing guide

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.96%. Comparing base (d7c561c) to head (632f988).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2014   +/-   ##
=======================================
  Coverage   86.96%   86.96%           
=======================================
  Files          98       98           
  Lines        3599     3599           
=======================================
  Hits         3130     3130           
  Misses        359      359           
  Partials      110      110           

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[thomaspoignant]

Oh good catch, I made a mistake when changing the image name.