Change version in DataPrepper Version class to 2.12 (#5638)

Signed-off-by: Krishna Kondaka <krishkdk@amazon.com>

Author: kkondaka

data-prepper-api/src/main/java/org/opensearch/dataprepper/model/configuration/DataPrepperVersion.java

@@ -6,7 +6,7 @@
 import java.util.regex.Pattern;
 
 public class DataPrepperVersion {
-    private static final String CURRENT_VERSION = "2.11";
+    private static final String CURRENT_VERSION = "2.12";
 
     private static final String FULL_FORMAT = "%d.%d";
     private static final String SHORTHAND_FORMAT = "%d";