docs: update USERS.md (#3688)

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Add curio to users.md

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Because we are using it :D

USERS.md

@@ -14,6 +14,7 @@ Here's a running list of some organizations using GoReleaser[^1]:
 1. [Conduit](https://www.conduit.io/)
 1. [CrowdStrike](https://www.crowdstrike.com)
 1. [Crusoe Cloud](https://crusoecloud.com)
+1. [Curio](https://curio.sh)
 1. [DeepSource](https://deepsource.io)
 1. [EVCC](https://evcc.io)
 1. [Fleet for osquery](https://fleetdm.com)