Update README.md (#614)

Author: Nicole00

README.md

@@ -11,7 +11,7 @@ Nebula Java is a Java client for developers to connect their projects to Nebula
 Please be noted that [nebula-JDBC](https://github.com/vesoft-inc/nebula-jdbc)(based on nebula-java)
 is the JDBC implementing for nebula graph.
 
-> **NOTE**: Nebula Java is not thread-safe.
+
 
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