docs: Add EA to USERS.md

[ragarcia26]

With 2 accepted PR's as well as active internal use, we'd like to put our name on here.

Checklist:

• Either (a) I've created an enhancement proposal and discussed it with the community, (b) this is a bug fix, or (c) this does not need to be in the release notes.
• The title of the PR states what changed and the related issues number (used for the release note).
• I've updated both the CLI and UI to expose my feature, or I plan to submit a second PR with them.
• Optional. My organization is added to USERS.md.
• I've signed the CLA and my build is green (troubleshooting builds).

Based off of:
#3508
and
#3667
and
argoproj/argo-helm#350
and our actual use of the product :)

[CLAassistant]

All committers have signed the CLA.

[codecov]

Codecov Report

Merging #3704 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3704   +/-   ##
=======================================
  Coverage   41.50%   41.50%           
=======================================
  Files         115      115           
  Lines       16540    16540           
=======================================
  Hits         6865     6865           
  Misses       8785     8785           
  Partials      890      890           

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[alexmt]

Thank you! 🎉

[dirtycajunrice]

@alexmt Just for complete explicitness, we have approval from legal for our name and link here on this page, but do not have approval for our logo to exist anywhere (e.g. on a webpage). Thank you for understanding in advance. Just wanted to make sure it was stated somewhere in-case more than the above is added!

[alexmt]

Thank you for heads up @dirtycajunrice . No problem at all.

Logos are added automatically to this web site: https://argoproj.github.io/ . The job that generates the page has no run yet. Updating script to make sure EA logo is not added.