Fix GCS Blob Repository 3rd Party Tests (#43030)

* We have to strip the trailing slash from child names here like we do for AWS
* closes #43029

plugins/repository-gcs/src/main/java/org/elasticsearch/repositories/gcs/GoogleCloudStorageBlobStore.java

@@ -30,7 +30,6 @@ import com.google.cloud.storage.Storage;
 import com.google.cloud.storage.Storage.BlobListOption;
 import com.google.cloud.storage.StorageBatch;
 import com.google.cloud.storage.StorageException;
-
 import org.elasticsearch.common.SuppressForbidden;
 import org.elasticsearch.common.blobstore.BlobContainer;
 import org.elasticsearch.common.blobstore.BlobMetaData;
@@ -50,11 +49,11 @@ import java.nio.channels.ReadableByteChannel;
 import java.nio.channels.WritableByteChannel;
 import java.nio.file.FileAlreadyExistsException;
 import java.nio.file.NoSuchFileException;
-import java.util.Map;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.atomic.AtomicReference;
 import java.util.stream.Collectors;
 
@@ -132,13 +131,15 @@ class GoogleCloudStorageBlobStore implements BlobStore {
     Map<String, BlobMetaData> listBlobsByPrefix(String path, String prefix) throws IOException {
         final String pathPrefix = buildKey(path, prefix);
         final MapBuilder<String, BlobMetaData> mapBuilder = MapBuilder.newMapBuilder();
-        SocketAccess.doPrivilegedVoidIOException(() -> {
-            client().get(bucketName).list(BlobListOption.prefix(pathPrefix)).iterateAll().forEach(blob -> {
-                assert blob.getName().startsWith(path);
-                final String suffixName = blob.getName().substring(path.length());
-                mapBuilder.put(suffixName, new PlainBlobMetaData(suffixName, blob.getSize()));
-            });
-        });
+        SocketAccess.doPrivilegedVoidIOException(
+            () -> client().get(bucketName).list(BlobListOption.currentDirectory(), BlobListOption.prefix(pathPrefix)).iterateAll().forEach(
+                blob -> {
+                    assert blob.getName().startsWith(path);
+                    if (blob.isDirectory() == false) {
+                        final String suffixName = blob.getName().substring(path.length());
+                        mapBuilder.put(suffixName, new PlainBlobMetaData(suffixName, blob.getSize()));
+                    }
+                }));
         return mapBuilder.immutableMap();
     }
 
@@ -150,7 +151,9 @@ class GoogleCloudStorageBlobStore implements BlobStore {
                 blob -> {
                     if (blob.isDirectory()) {
                         assert blob.getName().startsWith(pathStr);
-                        final String suffixName = blob.getName().substring(pathStr.length());
+                        assert blob.getName().endsWith("/");
+                        // Strip path prefix and trailing slash
+                        final String suffixName = blob.getName().substring(pathStr.length(), blob.getName().length() - 1);
                         if (suffixName.isEmpty() == false) {
                             mapBuilder.put(suffixName, new GoogleCloudStorageBlobContainer(path.add(suffixName), this));
                         }
@@ -312,11 +315,6 @@ class GoogleCloudStorageBlobStore implements BlobStore {
         if (blobNames.isEmpty()) {
             return;
         }
-        // for a single op submit a simple delete instead of a batch of size 1
-        if (blobNames.size() == 1) {
-            deleteBlob(blobNames.iterator().next());
-            return;
-        }
         final List<BlobId> blobIdsToDelete = blobNames.stream().map(blob -> BlobId.of(bucketName, blob)).collect(Collectors.toList());
         final List<BlobId> failedBlobs = Collections.synchronizedList(new ArrayList<>());
         final StorageException e = SocketAccess.doPrivilegedIOException(() -> {