Update README.md

Author: gkorland

README.md

@@ -4,6 +4,7 @@
 [![Maven Central](https://maven-badges.herokuapp.com/maven-central/com.redislabs/jredisgraph/badge.svg)](https://maven-badges.herokuapp.com/maven-central/com.redislabs/jredisgraph)
 [![Javadocs](https://www.javadoc.io/badge/com.redislabs/jredisgraph.svg)](https://www.javadoc.io/doc/com.redislabs/jredisgraph)
 [![Codecov](https://codecov.io/gh/RedisGraph/JRedisGraph/branch/master/graph/badge.svg)](https://codecov.io/gh/RedisGraph/JRedisGraph)
+[![Language grade: Java](https://img.shields.io/lgtm/grade/java/g/RedisGraph/JRedisGraph.svg?logo=lgtm&logoWidth=18)](https://lgtm.com/projects/g/RedisGraph/JRedisGraph/context:java)
 [![Known Vulnerabilities](https://snyk.io/test/github/RedisGraph/JRedisGraph/badge.svg?targetFile=pom.xml)](https://snyk.io/test/github/RedisGraph/JRedisGraph?targetFile=pom.xml)
 
 # JRedisGraph