Create Bootstrap Paging Links using Ajax

Question

    $.ajax({
        type: "POST",
        url: "php/crud.php",
        dataType: "json",
        data: {qtd_registros: 3, pagina: 1},
      success:function(dados){
       var paginacao = '<nav><ul class="pagination justify-content-center"><li class="page-item"><a class="page-link" href="index.html?pagina=0" aria-label="Previous"><span aria-hidden="true">&laquo;</span><span class="sr-only">Previous</span></a></li>';


          for(var i=0;i<dados.num_paginas;i++){
              if(pagina == i){$('#pag').addClass("active");}
           var soma = parseInt(1) + i;
           paginacao += '<li class="page-item" <a class="page-link" href="index.html?pagina='+i+'">'+soma+'</a></li>';
               }
           var links = dados.num_paginas - 1;
           paginacao += '<li class="page-item"><a class="page-link" href="index.html?pagina='+links+'" aria-label="Next"><span aria-hidden="true">&raquo;</span><span class="sr-only">Next</span></a></li></ul></nav>';

    $('table').after(paginacao);

  }
    });

In this case the number of the links are generated but not as links, somehow I do not know because when I check the bootstrap class 4.1 class="page-link" is not in the link appears like this <li class="page-item" <a="" href="index.html?pagina=1">2</li>

Dai as not having the class in the link the same appears as a text.