Adding Version check

Author: Tarun-kishore

src/main/kotlin/org/opensearch/indexmanagement/snapshotmanagement/model/ExplainSMPolicy.kt

@@ -5,6 +5,7 @@
 
 package org.opensearch.indexmanagement.snapshotmanagement.model
 
+import org.opensearch.Version
 import org.opensearch.core.common.io.stream.StreamInput
 import org.opensearch.core.common.io.stream.StreamOutput
 import org.opensearch.core.common.io.stream.Writeable
@@ -36,10 +37,15 @@ data class ExplainSMPolicy(
     override fun toXContent(builder: XContentBuilder, params: ToXContent.Params): XContentBuilder {
         metadata?.let {
             builder
-                .optionalField(SMMetadata.CREATION_FIELD, it.creation)
                 .optionalField(SMMetadata.DELETION_FIELD, it.deletion)
                 .field(SMMetadata.POLICY_SEQ_NO_FIELD, it.policySeqNo)
                 .field(SMMetadata.POLICY_PRIMARY_TERM_FIELD, it.policyPrimaryTerm)
+
+            if (Version.CURRENT > Version.V_3_3_0) {
+                builder.optionalField(SMMetadata.CREATION_FIELD, it.creation)
+            } else {
+                builder.field(SMMetadata.CREATION_FIELD, it.creation)
+            }
         }
         return builder.field(SMPolicy.ENABLED_FIELD, enabled)
     }