Modified util_make_irect() to capture area more robustly;

[psambit9791]

Relates to issue #3163.

This updates updates the area of the rectangle based on the floating point. Instead of simply typecasting from float to int, this function now floors the coordinates for the top left corner and ceils the coordinates for the bottom right corner.

This allows the function to more robustly detect the rectangle.

[github-actions[bot]]

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[psambit9791]

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[julian-smith-artifex-com]

[I think that the failure of "Test quick" is due to a problem with the latest mupdf, and not this PR.]

[julian-smith-artifex-com]

I've rebased this PR to get latest changes that fix test_quick.