Mark as CI in Jamfile not command line

super-project also runs regression test, but they doesn't define that.

test/Jamfile

@@ -9,10 +9,19 @@
 #==============================================================================
 # bring in rules for testing
 import testing ;
+import os ;
 import ../../config/checks/config : requires ;
 
+if [ os.environ CI ]
+{
+    CI_DEFINES = <define>CI_SKIP_KNOWN_FAILURE=1 ;
+    CI_DEFINES += <define>RUNNING_ON_TRAVIS=1 ;   # for backward compatibility
+    CI_DEFINES += <define>RUNNING_ON_APPVEYOR=1 ; # for backward compatibility
+}
+
 project
     : requirements
+        $(CI_DEFINES)
     ;
 
 {