docs: Add argos in intro

docs/intro/index.md

@@ -55,6 +55,10 @@ For a more detailed introduction to Mermaid and some of its more basic uses, loo
 
 **Thanks to all involved, people committing pull requests, people answering questions and special thanks to Tyler Long who is helping me maintain the project 🙏**
 
+Our PR Visual Regression Testing is powered by [Argos](https://argos-ci.com/?utm_source=mermaid&utm_campaign=oss) with their generous Open Source plan. It makes the process of reviewing PRs with visual changes a breeze.
+
+[![Covered by Argos Visual Testing](https://argos-ci.com/badge-large.svg)](https://argos-ci.com?utm_source=mermaid&utm_campaign=oss)
+
 In our release process we rely heavily on visual regression tests using [applitools](https://applitools.com/). Applitools is a great service which has been easy to use and integrate with our tests.
 
 <a href="https://applitools.com/">

packages/mermaid/src/docs/intro/index.md

@@ -50,6 +50,10 @@ For a more detailed introduction to Mermaid and some of its more basic uses, loo
 
 **Thanks to all involved, people committing pull requests, people answering questions and special thanks to Tyler Long who is helping me maintain the project 🙏**
 
+Our PR Visual Regression Testing is powered by [Argos](https://argos-ci.com/?utm_source=mermaid&utm_campaign=oss) with their generous Open Source plan. It makes the process of reviewing PRs with visual changes a breeze.
+
+[![Covered by Argos Visual Testing](https://argos-ci.com/badge-large.svg)](https://argos-ci.com?utm_source=mermaid&utm_campaign=oss)
+
 In our release process we rely heavily on visual regression tests using [applitools](https://applitools.com/). Applitools is a great service which has been easy to use and integrate with our tests.
 
 <a href="https://applitools.com/">