eiru_civil_engineering/static/src/xml/add_task_invoice_expenses.xml

<?xml version="1.0" encoding="UTF-8"?>
<template>
    <t t-name="eiruAddInvoiceTask.Expenses">
        <button class="button-add-task-invoice-expenses oe_stat_button btn btn_default">
            <div class="stat_button_icon fa fa-tasks"></div>
            <div class="add-button-task">Tareas</div>
        </button>
    </t>
</template>