Ensure check box and radio button labels have the correct for attribute when using a custom id

[spohlenz]

This PR fixes the label's for attribute when using a custom id so that the label remains clickable.

check_box :check_box, id: "custom-id"

Previous result:

<div class="form-check">
  <input name="check_box" type="hidden" value="0" autocomplete="off">
  <input label="Check box" class="form-check-input" type="checkbox" value="1" name="check_box" id="custom-id">
  <label class="form-check-label" for="check_box">Check box</label>
</div>

New result:

<div class="form-check">
  <input name="check_box" type="hidden" value="0" autocomplete="off">
  <input label="Check box" class="form-check-input" type="checkbox" value="1" name="check_box" id="custom-id">
  <label class="form-check-label" for="custom-id">Check box</label>
</div>

[coveralls]

coverage: 91.443% (+0.02%) from 91.421%
when pulling b01d143 on fix-custom-checkbox-id
into 0e112ec on main.