add sample database page

[chili-chiu]

Description

Add publicly available (bio)image sample databases as further resources on napari.org.
Also to address this issue on napari.

Type of change

• Bug-fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

References

How has this been tested?

• example: the test suite for my feature covers cases x, y, and z
• example: all tests pass with my change

Final checklist:

• My PR is the minimum possible work for the desired functionality
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• If I included new strings, I have used trans. to make them localizable.
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[DragaDoncila]

@chili-chiu I love this so much, just requested minor changes. Keen to have this in 🎉

[chili-chiu]

thanks @DragaDoncila, addressed your two questions :)

[DragaDoncila]

Thanks for making those updates @chili-chiu !