Update marketplace-fees-and-commissions.md (#1090)

## Changes

Small PR to add shoes to the publishing advance list for paid and
limited shoes. Prices are referenced from here:
https://devforum.roblox.com/t/introducing-avatar-shoes/3591562

Credit to [@raskolibov](https://devforum.roblox.com/u/raskolibov/) for
bringing this documentation issue up in [this devforum
post](https://devforum.roblox.com/t/shoes-missing-from-publishing-advance-list/3632013).

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Author: sammygrey

content/en-us/marketplace/marketplace-fees-and-commissions.md

@@ -112,6 +112,11 @@ This publishing advance is dependent on the type of Marketplace item being sold:
     <td>1500</td>
     <td>10000</td>
   </tr>
+    <tr>
+    <td>Shoes</td>
+    <td>600</td>
+    <td>5000</td>
+  </tr>
 </tbody>
 </table>