Migration to QuPath 0.6.x

This release make the extension compatible with QuPath 0.6.x and fixes a bunch of bugs / features

Bug fix

• Enable to use MAC GPU option (thanks to @AlbertDominguez in #8)
• When running spotiflow on multiple channels, all the points for all the channels are now correctly displayed - fix #11
• Forcing minDistance parameter to be an integer number - fix #12
• Correctly handle waitFor() process on Mac systems - fix #15
• Try to separate UI code in a separate JavaFX thread - fix #15
• Remove points ouside parent shape - fix #14
• Fix compatibility with spotiflow 0.5.7 and 0.5.8 - fix #13
• Fix warning on null PathClass by using .resetPathClass() instead

New feature

• Saving temp images as OME-Zarr files (only from spotiflow 0.5.8) - fix #9 and #2
• Set options to clear child object or not
• Set option to save the builder

Refactor

• Add a supplementary folder layer in the temp dir to separate shapes between images
• Run spotiflow command only once, even if multiple channels/parents are selected
• Refactor savePredictionImages to cleanTempDir
• Update github actions