EventLogging: fix test2wiki configs; +CodeEditor

This patch updates the configuration of EventLogging on test2wiki to ensure it
does not attempt to record events against the production endpoints and enables
CodeEditor on Meta for the Schema NS (leaving $wgCodeEditorEnableCore disabled
for now.)

Change-Id: I7914cc6a7602fc11a186bfaa3aeea9c315f67a24