Add EPL 2.0 badge (#1862)

Signed-off-by: Marinov Avgustin <[email protected]>

README.md

@@ -8,6 +8,7 @@ Build:
 [![Build Status](https://github.com/eclipse-hawkbit/hawkbit/workflows/verify/badge.svg)](https://github.com/eclipse-hawkbit/hawkbit/actions/workflows/verify.yml)
 [![Quality Gate Status](https://sonarcloud.io/api/project_badges/measure?project=org.eclipse.hawkbit%3Ahawkbit-parent&metric=alert_status)](https://sonarcloud.io/summary/new_code?id=org.eclipse.hawkbit%3Ahawkbit-parent)
 [![Maven Central](https://img.shields.io/maven-central/v/org.eclipse.hawkbit/hawkbit-parent?color=blue)](https://maven-badges.herokuapp.com/maven-central/org.eclipse.hawkbit/hawkbit-parent)
+[![License](https://img.shields.io/badge/License-EPL%202.0-green.svg)](https://opensource.org/licenses/EPL-2.0)
 [![Lines of code](https://img.shields.io/badge/dynamic/xml.svg?label=Lines%20of%20code&url=https%3A%2F%2Fwww.openhub.net%2Fprojects%2Fhawkbit.xml%3Fapi_key%3D30bc3f3fad087c2c5a6a67a8071665ba0fbe3b6236ffbf71b7d20849f4a5e35a&query=%2Fresponse%2Fresult%2Fproject%2Fanalysis%2Ftotal_code_lines&colorB=lightgrey)](https://www.openhub.net/p/hawkbit)
 
 Docker: [![Docker](https://img.shields.io/docker/v/hawkbit/hawkbit-update-server/latest?color=blue)](https://hub.docker.com/r/hawkbit/hawkbit-update-server) [![Docker MYSQL](https://img.shields.io/docker/v/hawkbit/hawkbit-update-server/latest-mysql?color=blue)](https://hub.docker.com/r/hawkbit/hawkbit-update-server)