docs: Add SI Analytics to ArgoCD Users list

[JhoLee]

We're using ArgoCD to manage whole services in our K8S clusters very well. 👍🏽

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Note on DCO:

If the DCO action in the integration test fails, one or more of your commits are not signed off. Please click on the Details link next to the DCO action for instructions on how to resolve this.

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 included "Closes [ISSUE #]" or "Fixes [ISSUE #]" in the description to automatically close the associated issue.
• I've updated both the CLI and UI to expose my feature, or I plan to submit a second PR with them.
• Does this PR require documentation updates?
• I've updated documentation as required by this PR.
• Optional. My organization is added to USERS.md.
• I have signed off all my commits as required by DCO
• I have written unit and/or e2e tests for my change. PRs without these are unlikely to be merged.
• My build is green (troubleshooting builds).

[codecov]

Codecov Report

Base: 45.60% // Head: 45.60% // No change to project coverage 👍

Coverage data is based on head (087456f) compared to base (776d8f9).
Patch has no changes to coverable lines.

Additional details and impacted files

@@           Coverage Diff           @@
##           master   #11110   +/-   ##
=======================================
  Coverage   45.60%   45.60%           
=======================================
  Files         237      237           
  Lines       28914    28914           
=======================================
  Hits        13185    13185           
  Misses      13913    13913           
  Partials     1816     1816           

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[crenshaw-dev]

Thanks @JhoLee!