[BUG] Fix exception handling for global metadata upload

[dhwanilpatel]

Describe the bug
If there is any exception occur during global metadata upload, onFailure of completionActionListener will be invoked. Today it throws the GlobalMetadataTransferException from onResponse of action listener.

OpenSearch/server/src/main/java/org/opensearch/gateway/remote/RemoteClusterStateService.java

Lines 381 to 384 in 5bd413c

	LatchedActionListener completionListener = new LatchedActionListener<>(ActionListener.wrap(resp -> {
	logger.trace(String.format(Locale.ROOT, "GlobalMetadata uploaded successfully."));
	result.set(globalMetadataContainer.path().buildAsString() + globalMetadataFilename);
	}, ex -> { throw new GlobalMetadataTransferException(ex.getMessage(), ex); }), latch);

For async writes, this action listener can be invoked from different thread as well. So exception thrown from action listener will be lost and response of writeGlobalMetadata will become null and corrupt the manifest files.

Fix
We will need to store the referance of the exception from action listener, and need checks on it before returning from writeGlobalMetadata