$('input#processLabel').keypress(function() {
  const dInput = $(this).val().replace(",",".");
  $(this).val(dInput);
});

<div id="upload_div" class="mt-3">
      <input class="inbox form-control" type="text" name="processLabel[]" id="processLabel" value="" onkeypress="return event.charCode >= 40 && event.charCode <= 57">
  </div>