If this was your only self employed work, then you won't need to worry about self-employment taxes since the total amount is under $400. In this case, you will be able to enter the income as just miscellaneous income.
If you did have more self-employment income, then you will need to add this income as a Schedule C business to include it in your net self-employment income calculations. Type “Schedule C" in the search box, top right of your screen, then click the magnifying glass. Click the "jump to schedule c" link in the search results. You will arrive at the Your Business summary page where you can add/edit a business for Rover. Proceed through and add the income as general cash income.