Defferred footnotes and spread break problem

[MurakamiShinyu]

Test case: footnotes_and_page_floats.html

Test with Vivliostyle Viewer v2.41.0:

• https://vivliostyle.github.io/viewer/v2.41.0/#src=https://raw.githubusercontent.com/vivliostyle/vivliostyle.js/master/packages/core/test/files/footnotes/footnotes_and_page_floats.html

Screenshot (Pages 4-7):

Problem:

• Footnote 4 should be deferred to Page 5, but it is defferred to Page 6 skipping the blank page (Page 5) generated by the spread break section { break-after: left; }.