Fixes getting snapshot status checks for preventing duplicate entries

from both current snapshots (cluster state) and repository snapshots
(on storage).

Author: Ali Beyad

core/src/main/java/org/elasticsearch/action/admin/cluster/snapshots/status/TransportSnapshotsStatusAction.java

@@ -207,15 +207,14 @@ private SnapshotsStatusResponse buildResponse(SnapshotsStatusRequest request, Li
                 .filter(s -> requestedSnapshotNames.contains(s.getName()))
                 .collect(Collectors.toMap(SnapshotId::getName, Function.identity()));
             for (final String snapshotName : request.snapshots()) {
+                if (currentSnapshotNames.contains(snapshotName)) {
+                    // we've already found this snapshot in the current snapshot entries, so skip over
+                    continue;
+                }
                 SnapshotId snapshotId = matchedSnapshotIds.get(snapshotName);
                 if (snapshotId == null) {
-                    if (currentSnapshotNames.contains(snapshotName)) {
-                        // we've already found this snapshot in the current snapshot entries, so skip over
-                        continue;
-                    } else {
-                        // neither in the current snapshot entries nor found in the repository
-                        throw new SnapshotMissingException(repositoryName, snapshotName);
-                    }
+                    // neither in the current snapshot entries nor found in the repository
+                    throw new SnapshotMissingException(repositoryName, snapshotName);
                 }
                 SnapshotInfo snapshotInfo = snapshotsService.snapshot(repositoryName, snapshotId);
                 List<SnapshotIndexShardStatus> shardStatusBuilder = new ArrayList<>();