JSFiddle - React, Tailwind, and code Playground

HTML

<span class="select-wrapper">
    <select class="form-control no-radius">
        <option value="1">1</option>
        <option value="2">2</option>
        <option value="3">3</option>
    </select>
</span>

CSS

select.no-radius{
    border:none;
}    
.select-wrapper{
    border: 1px solid black;
    border-radius: 0px;
}