Change reference to collections-c repo.

.gitmodules

@@ -11,5 +11,5 @@
     url = https://github.com/centaurean/spookyhash.git
 [submodule "ext/collections-c"]
     path = ext/collections-c
-    url = https://github.com/scossu/Collections-C.git
+    url = https://github.com/scossu/lsup-collections-c.git
     branch = lsup

ext/collections-c

@@ -1 +1 @@
-Subproject commit 8470a781a9958ccdc66c32b60714bb7e52b75a8d
+Subproject commit 06660db3b3834a2119c3cccff04268f91f660604