docs: fix post merge badge (#7532)

Signed-off-by: sspaink <[email protected]>

Author: sspaink

README.md

@@ -1,6 +1,6 @@
 # ![logo](./logo/logo-144x144.png) Open Policy Agent
 
-[![Build Status](https://github.com/open-policy-agent/opa/workflows/Post%20Merge/badge.svg?branch=main)](https://github.com/open-policy-agent/opa/actions) [![Go Report Card](https://goreportcard.com/badge/open-policy-agent/opa)](https://goreportcard.com/report/open-policy-agent/opa) [![CII Best Practices](https://bestpractices.coreinfrastructure.org/projects/1768/badge)](https://bestpractices.coreinfrastructure.org/projects/1768) [![Netlify Status](https://api.netlify.com/api/v1/badges/4a0a092a-8741-4826-a28f-826d4a576cab/deploy-status)](https://app.netlify.com/sites/openpolicyagent/deploys)
+[![Build Status](https://github.com/open-policy-agent/opa/workflows/Post%20Merge/badge.svg)](https://github.com/open-policy-agent/opa/actions) [![Go Report Card](https://goreportcard.com/badge/open-policy-agent/opa)](https://goreportcard.com/report/open-policy-agent/opa) [![CII Best Practices](https://bestpractices.coreinfrastructure.org/projects/1768/badge)](https://bestpractices.coreinfrastructure.org/projects/1768) [![Netlify Status](https://api.netlify.com/api/v1/badges/4a0a092a-8741-4826-a28f-826d4a576cab/deploy-status)](https://app.netlify.com/sites/openpolicyagent/deploys)
 
 Open Policy Agent (OPA) is an open source, general-purpose policy engine that enables unified, context-aware policy enforcement across the entire stack.