message: docs: correct literal string example
  Change literal string example `pi` to `'pi'`.
  PR Close
diff: @@ -173,7 +173,7 @@ Define metadata objects with the following limited syntax:
  <td><code>`pie is ${multiplier} times better than cake`</code></td>
  <tr>
  <td>Literal string</td>
  - <td><code>pi</code></td>
  + <td><code>'pi'</code></td>
  </tr>
  <tr>
  <td>Literal number</td>
  