Remove broken Conformance badge from README (#1719)

Problem: Now that the Conformance tests run as part of the CI workflow, the badge for the Conformance workflow no longer works.

Solution: Remove this badge in favor of the CI badge.

README.md

@@ -1,7 +1,6 @@
 [![OpenSSF Scorecard](https://api.securityscorecards.dev/projects/github.com/nginxinc/nginx-gateway-fabric/badge)](https://api.securityscorecards.dev/projects/github.com/nginxinc/nginx-gateway-fabric)
 [![FOSSA Status](https://app.fossa.com/api/projects/custom%2B5618%2Fgithub.com%2Fnginxinc%2Fnginx-gateway-fabric.svg?type=shield)](https://app.fossa.com/projects/custom%2B5618%2Fgithub.com%2Fnginxinc%2Fnginx-gateway-fabric?ref=badge_shield)
 [![Continuous Integration](https://github.com/nginxinc/nginx-gateway-fabric/actions/workflows/ci.yml/badge.svg)](https://github.com/nginxinc/nginx-gateway-fabric/actions/workflows/ci.yml)
-[![Conformance Testing](https://github.com/nginxinc/nginx-gateway-fabric/actions/workflows/conformance.yml/badge.svg)](https://github.com/nginxinc/nginx-gateway-fabric/actions/workflows/conformance.yml)
 [![Go Report Card](https://goreportcard.com/badge/github.com/nginxinc/nginx-gateway-fabric)](https://goreportcard.com/report/github.com/nginxinc/nginx-gateway-fabric)
 [![codecov](https://codecov.io/gh/nginxinc/nginx-gateway-fabric/graph/badge.svg?token=32ULC8F13Z)](https://codecov.io/gh/nginxinc/nginx-gateway-fabric)
 [![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/nginxinc/nginx-gateway-fabric?logo=github&sort=semver)](https://github.com/nginxinc/nginx-gateway-fabric/releases/latest)