Fix Icon Picker rendering empty when one item should be rendered

[fabiankaegy]

Description of the Change

The code to retrieve the icon to be rendered in the icon grid had a logical error in it. When it tried to calculate the index of the icon to render based on the position of the icon in the virtualized grid, the maths was adding +1 at the end to make its index human-readable instead of index 0 which we would need to actually render the correct icon.

This issue means that regardless of the state of the icon picker, the first icon in the list is not rendered. This becomes most obvious when there only is one icon like when you are searching and there is only one match.

Closes #248

How to test the Change

1. Insert Icon Picker
2. Search for an icon name that only occurs once. / Alternatively only register one singular icon

Changelog Entry

Fixed - Empty rendering of first item in Icon Picker due to index 0

Credits

Props @psorensen @TylerB24890 @fabiankaegy

Checklist:

• I agree to follow this project's Code of Conduct.
• I have updated the documentation accordingly.
• I have added tests to cover my change.
• All new and existing tests pass.

[fabiankaegy]

I have pushed this fix to NPM as an alpha version so we can all test it on actual projects. To pull down the specific version run

npm i @10up/block-components@1.16.2-icon-picker.0

[github-actions]

Size Change: -2 B (0%)

Total Size: 53.5 kB

Filename	Size	Change
dist/index.js	53.5 kB	-2 B (0%)

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[Antonio-Laguna]

@fabiankaegy this LGTM!

[TylerB24890]

Confirmed this seems to be working for me!