Spreadsheet styling

[andrewtpham]

What issue(s) does this PR resolve?

Fixes styling when dragging to fill in the spreadsheet component:

Considerations and implementation

Issues still facing:

• When dragging top to bottom then back up while holding the drag to fill icon, the selected cell jumps by 1 px up.
• When adding multiple rows, it looks like every other row has an additional 1px whitespace at the bottom.

How to test

1. Add a few additional rows into the spreadsheet
2. Select a cell and drag from top to bottom
3. Hold the drag to fill icon and go back and forth and you can see that the highlighted area is larger than the cells it is highlights

Test(s) added

N/A

Mentions?

@michaelbukachi @ninetteadhikari

[ninetteadhikari]

looks good ✅

[ninetteadhikari]

there is still a slight gap in the last row.. but maybe we can live with it? 🤷