Update version in Maven usage snippet

Signed-off-by: Niklas <nscuro@protonmail.com>

Author: nscuro

README.md

@@ -21,7 +21,7 @@ Maven Usage
 <dependency>
     <groupId>org.cyclonedx</groupId>
     <artifactId>cyclonedx-core-java</artifactId>
-    <version>11.0.1</version>
+    <version>12.0.0</version>
 </dependency>
 ```