Exclude experimental/logging/example from the main folly_base rule

Summary: It's an example, not part of the main Folly library.

Reviewed By: yfeldblum

Differential Revision: D5304985

fbshipit-source-id: 7cfb95da5795af61e9307882f71836ef7fa5a463

CMakeLists.txt

@@ -81,6 +81,7 @@ REMOVE_MATCHES_FROM_LISTS(files hfiles
     "/experimental/exception_tracer/"
     "/experimental/hazptr/bench/"
     "/experimental/hazptr/example/"
+    "/experimental/logging/example/"
     "/experimental/symbolizer/"
     "/futures/exercises/"
     "/test/"