prep for release of 3.1.3

Author: Crim

README.md

@@ -12,7 +12,7 @@ This client library is released on Maven Central.  Add a new dependency to your
 <dependency>
     <groupId>org.sourcelab</groupId>
     <artifactId>kafka-connect-client</artifactId>
-    <version>3.1.2</version>
+    <version>3.1.3</version>
 </dependency>
 ```
 

pom.xml

@@ -6,7 +6,7 @@
 
     <groupId>org.sourcelab</groupId>
     <artifactId>kafka-connect-client</artifactId>
-    <version>3.1.3-SNAPSHOT</version>
+    <version>3,1,3</version>
     <packaging>jar</packaging>
 
     <!-- Require Maven 3.3.9 -->