Remove co_spawn example

Author: vinniefalco

example/CMakeLists.txt

@@ -10,4 +10,3 @@
 
 add_subdirectory(client)
 add_subdirectory(server)
-add_subdirectory(cpp20)

example/Jamfile

@@ -10,4 +10,3 @@
 
 build-project client ;
 build-project server ;
-build-project cpp20 ;