Per my research, there are no official articles to describe how to ignore the failure caused by hidden folders. As a workaround, as the migration report file extension is csv (SummaryReport.csv and FailureSummary.csv), we could use the filter feature in csv by the "Message" and "Error code" column, which include failed reason detail description and failed reason errorcode.
For more information about Failure Summary Report, you could refer to:
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