chore: minor build user agent from version string

Author: rhamzeh

src/main/java/dev/openfga/sdk/api/configuration/Configuration.java

@@ -33,7 +33,7 @@ public class Configuration implements BaseConfiguration {
     public static final String VERSION = "0.8.2-beta.1";
 
     private static final String DEFAULT_API_URL = "http://localhost:8080";
-    private static final String DEFAULT_USER_AGENT = "openfga-sdk java/0.8.2-beta.1";
+    private static final String DEFAULT_USER_AGENT = "openfga-sdk java/" + VERSION;
     private static final Duration DEFAULT_READ_TIMEOUT = Duration.ofSeconds(10);
     private static final Duration DEFAULT_CONNECT_TIMEOUT = Duration.ofSeconds(10);