Add exclusion for new incubator-openwhisk perf. tests. (#26)

diff --git a/scancode/ASF-Release.cfg b/scancode/ASF-Release.cfg
index c4014a9..4cf26bb 100644
--- a/scancode/ASF-Release.cfg
+++ b/scancode/ASF-Release.cfg
@@ -40,6 +40,9 @@
 # incubator-openwhisk binary artifact exclusions
 bin
 
+# incubator-openwhisk performance test exclusions
+performance
+
 # Jenkins/test generated reports
 tests/build/reports