gdalwarp: fix crash/infinite loop when using -tr one a 1x1 blank raster (3.8.0 regression)

[rouault]

Fixes regression introduced by #7911
Test case: https://lists.osgeo.org/pipermail/gdal-dev/2024-September/059512.html

Fixes #10827

[coveralls]

coverage: 69.372% (+0.001%) from 69.371%
when pulling 7f674a8 on rouault:fix_gdalwarp_one_one_blank_edge
into 2742d2b on OSGeo:master.

[misev]

I applied this commit to the release/3.8 branch and compiled it on Ubuntu 24.04 with cmake config

cmake ../gdal -DGDAL_BUILD_OPTIONAL_DRIVERS=OFF -DOGR_BUILD_OPTIONAL_DRIVERS=OFF

but it doesn't seem to work well:

$ export LD_LIBRARY_PATH="/usr/local/lib:$LD_LIBRARY_PATH"
$ ldd /usr/local/bin/gdalwarp 2>&1 | grep gdal -i
    libgdal.so.34 => /usr/local/lib/libgdal.so.34 (0x00007fc412c00000)
    
$ /usr/local/bin/gdalwarp test.vrt -t_srs EPSG:32631 -tr 1000 1000 -of VRT output.vrt -overwrite
Creating output file that is 0P x 0L.
ERROR 1: Attempt to create 0x0 dataset is illegal,sizes must be larger than zero.

[rouault]

but it doesn't seem to work well:

I've updated the PR to also handle the case where -tap is not specified