Add OSSF scorecard badge (#7073)

Author: trask

README.md

@@ -1,8 +1,11 @@
 # OpenTelemetry Java
+
 [![Continuous Build][ci-image]][ci-url]
 [![Coverage Status][codecov-image]][codecov-url]
 [![Maven Central][maven-image]][maven-url]
 [![Reproducible Builds](https://img.shields.io/endpoint?url=https://raw.githubusercontent.com/jvm-repo-rebuild/reproducible-central/master/content/io/opentelemetry/java/badge.json)](https://github.com/jvm-repo-rebuild/reproducible-central/blob/master/content/io/opentelemetry/java/README.md)
+[![OpenSSF Scorecard](https://api.scorecard.dev/projects/github.com/open-telemetry/opentelemetry-java/badge)](https://scorecard.dev/viewer/?uri=github.com/open-telemetry/opentelemetry-java)
+[![OpenSSF Best Practices](https://www.bestpractices.dev/projects/9991/badge)](https://www.bestpractices.dev/projects/9991)
 
 `opentelemetry-java` is the home of the Java implementation of the OpenTelemetry API for recording
 telemetry, and SDK for managing telemetry recorded by the API.