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I am not reproduce the same issue that you're having. It is working properly on my side.
However if you are still having that issue you can add the CSS code below from designer:
margin-bottom: 0 !important;
padding-bottom: 0 !important;
As an alternatively, You can decrease your line spacing of your form as you see below.
If it doesn't work please let us know. We can solve your issue with different way.