Pytest-image-snapshot

* Add --image-snapshot-fail-if-missing
* Update Python versions and add GitHub actions
* Fail on missing snapshot

* feat: improve error messages ([5d622bc](https://github.com/bmihelac/pytest-image-snapshot/commit/5d622bc))

* fix: default threshold should not be None ([470c4b0](https://github.com/bmihelac/pytest-image-snapshot/commit/470c4b0))
* fix: remove python 3.5 from supported versions ([7d08578](https://github.com/bmihelac/pytest-image-snapshot/commit/7d08578))
* doc: use threshold in playwright example ([281b7dd](https://github.com/bmihelac/pytest-image-snapshot/commit/281b7dd))

* doc: fix README links ([feac8ef](https://github.com/bmihelac/pytest-image-snapshot/commit/feac8ef))

Features

* add threshold option for anti-aliasing pixel detection ([ce7b303](https://github.com/bmihelac/pytest-image-snapshot/commit/ce7b303fa41cad906995f11ad60719c379ced935))

Bug Fixes

* convert RGBA images to RGB for Pillow < 10 ([a1086ad](https://github.com/bmihelac/pytest-image-snapshot/commit/a1086adb10f2d2e0c6f03b59835982974653b12a))
* setup.py long_description_content_type ([f92004e](https://github.com/bmihelac/pytest-image-snapshot/commit/f92004ebe2821787801641789e957c4f019ed2ef))