Use sahara.conf.sample instead of old one

Sahara internals was updated, now we can use correct conf sample.

Change-Id: Ia8d99c2742785c3b5c724617a5dfc2880624a03f
diff --git a/lib/sahara b/lib/sahara
index 4cb04ec..38b4ecd 100644
--- a/lib/sahara
+++ b/lib/sahara
@@ -106,8 +106,7 @@
     sudo chown $STACK_USER $SAHARA_CONF_DIR
 
     # Copy over sahara configuration file and configure common parameters.
-    # TODO(slukjanov): rename when sahara internals will be updated
-    cp $SAHARA_DIR/etc/savanna/savanna.conf.sample $SAHARA_CONF_FILE
+    cp $SAHARA_DIR/etc/sahara/sahara.conf.sample $SAHARA_CONF_FILE
 
     # Create auth cache dir
     sudo mkdir -p $SAHARA_AUTH_CACHE_DIR