Adds support to provide tags with value in Gauge metric

Signed-off-by: Gagan Juneja <gjjuneja@amazon.com>

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/TaggedMeasurement.java

@@ -16,7 +16,7 @@
  * @opensearch.experimental
  */
 @ExperimentalApi
-public class TaggedMeasurement {
+public final class TaggedMeasurement {
     private final Double value;
     private final Tags tags;