Spreadsheet gets stuck loading some files

[edler-san]

I tested the file from https://vaadin.com/forum/thread/17814053/hello-i-have-problem-with-certain-xlsx-files-when-read-it-s-infinite-and and the spreadsheet seems indeed to get stuck(I let it run for 15+ minutes) - yet printing the content out with POI (4.1.0) works without issues. I tested with Spreadsheets 2.1 and 3.0.0.alpha1. No exceptions were thrown.

Fully working example attached. sheet-test.zip