Add an OpenSSF badge to README.md

Author: MrAlias

README.md

@@ -4,6 +4,7 @@
 [![codecov.io](https://codecov.io/gh/open-telemetry/opentelemetry-go/coverage.svg?branch=main)](https://app.codecov.io/gh/open-telemetry/opentelemetry-go?branch=main)
 [![PkgGoDev](https://pkg.go.dev/badge/go.opentelemetry.io/otel)](https://pkg.go.dev/go.opentelemetry.io/otel)
 [![Go Report Card](https://goreportcard.com/badge/go.opentelemetry.io/otel)](https://goreportcard.com/report/go.opentelemetry.io/otel)
+[![OpenSSF Scorecard](https://api.scorecard.dev/projects/github.com/open-telemetry/opentelemetry-go/badge)](https://scorecard.dev/viewer/?uri=github.com/open-telemetry/opentelemetry-go)
 [![Slack](https://img.shields.io/badge/slack-@cncf/otel--go-brightgreen.svg?logo=slack)](https://cloud-native.slack.com/archives/C01NPAXACKT)
 
 OpenTelemetry-Go is the [Go](https://golang.org/) implementation of [OpenTelemetry](https://opentelemetry.io/).