Image alignment can be easily modified via the Space feature:
- Click Build on the left sidebar of the Site Editor.
- In Features, click the Layout dropdown.
- Drag the Space item and drop it into a block.
- Adjust the size by dragging the lower side of the feature.
To delete the extra Space between images:
- Hover over the Space area, and click x on a panel.
- Adjust the size by dragging the lower side.