[Docs v4.1] Input group - missing ID for aria-describedby

[AlessandroVecchi]

https://getbootstrap.com/docs/4.1/components/input-group/#button-addons

aria-describedby="basic-addon1"
aria-describedby="basic-addon2"

<div class="input-group mb-3">
  <div class="input-group-prepend">
    <button class="btn btn-outline-secondary" type="button">Button</button>
  </div>
  <input type="text" class="form-control" placeholder="" aria-label="" aria-describedby="basic-addon1"> 
</div>

<div class="input-group mb-3">
  <input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username" aria-describedby="basic-addon2">
  <div class="input-group-append">
    <button class="btn btn-outline-secondary" type="button">Button</button>
  </div>
</div>

<div class="input-group mb-3">
  <div class="input-group-prepend">
    <button class="btn btn-outline-secondary" type="button">Button</button>
    <button class="btn btn-outline-secondary" type="button">Button</button>
  </div>
  <input type="text" class="form-control" placeholder="" aria-label="" aria-describedby="basic-addon1"> <---
</div>

<div class="input-group">
  <input type="text" class="form-control" placeholder="Recipient's username" aria-label="Recipient's username" aria-describedby="basic-addon2">
  <div class="input-group-append">
    <button class="btn btn-outline-secondary" type="button">Button</button>
    <button class="btn btn-outline-secondary" type="button">Button</button>
  </div>
</div>

[patrickhlauke]

Good spot. that whole section seems a bit messed-up as a result of multiple changes, edits, copy/pastes over the years. Will be fixed by #26551