fix(pd): partition IDs always empty in Shards List (apache#2596)

Author: haohao0103

hugegraph-pd/hg-pd-service/src/main/java/org/apache/hugegraph/pd/rest/PartitionAPI.java

@@ -236,6 +236,7 @@ public RestApiResponse getPartitions() {
                         role = shard.getRole();
                         address = pdRestService.getStore(
                                 shard.getStoreId()).getAddress();
+                        partitionId = partition.getId();
                         if (finalShardStats.containsKey(shard.getStoreId())) {
                             state = finalShardStats.get(shard.getStoreId()).getState().toString();
                             progress = finalShardStats.get(shard.getStoreId()).getProgress();