Fix property name typo in DrydockResource

Summary: `$capbilities` has a typo.

Test Plan: Slowly spell the word "capabilities"; compare with the top of the file.

Reviewers: O1 Blessed Committers, valerio.bozzolan

Reviewed By: O1 Blessed Committers, valerio.bozzolan

Subscribers: tobiaswiese, valerio.bozzolan, Matthew, Cigaryno

Differential Revision: https://we.phorge.it/D25714

src/applications/drydock/storage/DrydockResource.php

@@ -69,7 +69,7 @@ final class DrydockResource extends DrydockDAO
   }
 
   public function getCapability($key, $default = null) {
-    return idx($this->capbilities, $key, $default);
+    return idx($this->capabilities, $key, $default);
   }
 
   public function getInterface(DrydockLease $lease, $type) {