cloud example coredump when specify options max_log_file_size

[wangshao1]

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Expected behavior

Actual behavior

when specify options.max_log_file_size to a none zero value, process coredumps because of a fail assert about cloud_manifest.
Here is the stack

When rocksdb open and options.info_log is nullptr, rocksdb will create a autorolllogger，autorolllogger's construct function will find exist old LOG files by calling env->filesystem()->GetChildren(). In rocksdb-cloud, env->filesystem is cloudFileSystem which will do RemapFilename for some files, but cloud_manifest has not been loaded yet.
In my opinion, the LOGs will not been uploaded to cloud and not need to be synchonized either. So maybe we can pass filesystem::Default() when constructing autorolllogger? Or add extra member varable in env to represent base_fs_?

Steps to reproduce the behavior

specify options.max_log_file_size or options.log_file_time_to_roll to a none zero value.
run example in cloud sub dir twice(To make the local_dir is not empty).