Include current directoy in asdf source registry

My dev setup has the project's entire parent directory included in the
source registry, which not everyone has. Add the directory here to see
if it fixes a build issue.

build-mahogany.lisp

@@ -6,7 +6,7 @@
 ;; to be used instead of anything that asdf can find in our environment
 (asdf:initialize-source-registry
  `(:source-registry
-   (:directory ,(merge-pathnames (uiop/os:getcwd) #P"src"))
+   (:directory ,(uiop/os:getcwd))
    (:tree ,(merge-pathnames (uiop/os:getcwd) #P"dependencies"))
    ;; Use whatever the user has configured in their environment to find the rest.
    :inherit-configuration))