Rename plugin to ExternalResources

Change-Id: Ieb7bee4929e4351316ad19d9bcd3752d466437da
diff --git a/go.mod b/go.mod
index 649e774..7260720 100644
--- a/go.mod
+++ b/go.mod
@@ -1,4 +1,4 @@
-module github.com/KorAP/Kalamar-Plugin-ExternalSale
+module github.com/KorAP/Kalamar-Plugin-ExternalResources
 
 go 1.19