docs: add ci status badge to readme
+[![Verify Build Workflow](https://github.com/apiman/apiman-developer-portal/actions/workflows/verify.yml/badge.svg)](https://github.com/apiman/apiman-developer-portal/actions/workflows/verify.yml)
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# Apiman Developer Portal
> A developer portal for Apiman! Allow developers to access your APIs. Developers can view and test your APIs to develop their own apps.
