Remove $wgJavaScriptTestConfig
The config variable itself and the documentation property were added
in MediaWiki 1.19 (r107919 /
c447423593).
The testswarm-injectjs propert was added in MediaWiki 1.20 (
5e590be3d6).
We never actually ended up using TestSwarm, and this variable
is not used anywhere I can see.
Having a configuration variable for a documentation page seems
odd. I can't find another instance of this. As it's tied to development
(not for users of the wiki), link to mediawiki.org direcly.
Change-Id: Ib16607683a293b6d6661ed0411dad9a3ff551a08