Rename hdfs config authorization.provider.bypass.users to attributes.provider.bypass.users

HDFS-12357 introduced a new config 'dfs.namenode.inode.attributes.provider.bypass.users' to allow configured users to bypass external attributes provider. However, after committing HDFS-12357, noticed that a different config name 'dfs.namenode.authorization.provider.bypass.users' is put into hdfs-default.xml, which is different than what used in java code. And this is not correct.

Creating this jira to fix the hdfs-default.xml one to be consistent with the implementation