how to put two words in a button on single line

.group {
  display: flex;
  flex-direction: row;
  border: 1px solid black;
  max-width: 100px;
}

.group > div {
  border: 1px solid green;
  margin: 2px;
}

<div class="group">
  <div>Mandatory Documents</div>
  <div><button>Button</button></div>
</div>
<br>
<div class="group">
  <div>Mandatory Documents</div>
  <div><button>Button</button></div>
</div>