993 progress: 3 more files converted (stac-utils#1532)

* 993 convert test_custom.py to pytest

* 993 remove maxDiff & convert assertions in test_eo.py

* 993 convert migration & band tests to pytest

* 993 prep EOTest for pytest conversion

* 993 convert EOTest to pytest

* 993 move test_eo cassettes to new names

* 993 fix straggler

* 993 start test_pointcloud.py by converting assertions

* 993 make fixtures in test_pointcloud.py

* 993 convert a few tests to pytest

* 993 declass PointCloudTest (nonfunctional)

* 993 move cassettes to reflect new test names

* 993 convert rest of PointcloudTest tests

* 993 conversion for summaries tests

* 993 ruff got tough with the code

* 993 mypy also gettin rough

Author: teks