verify_segmentation: make bulletproof

[remtav]

Verify_segmentation.py script is meant to be the first step when starting a project with new data. This script should be able to complete (i.e. write it's csv report) no matter how bad certain data is in the input csv. Two most probable examples of bad data:

• invalid input raster such as a stac item
• invalid ground truth file

Adding a couple try/except statements should do it. Also, errors should be carried over to the final report, therefore saved in variables such as raster_errors = [error1, error2], etc.