fallback for truncated ListObjects V1 responses without NextMarker

[387809109]

Description of Changes

For non-AWS endpoints, netCDF-Java 5.9.1 selected ListObjects V1.

The original pagination logic was:

String continuationToken =
    useV2
        ? responseV2.nextContinuationToken()
        : responseV1.nextMarker();
updateObjectList(continuationToken);

A direct AWS SDK ListObjects V1 request for Swift returned:

count=1000
isTruncated=true
nextMarker=null

The page was valid and truncated, but Swift did not return NextMarker, therefore netCDF-Java repeatedly requested the first page.

changed that part to add a fallback for truncated ListObjects V1 responses without NextMarker

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