Requirement: run API integration tests on changes against mediawiki core (at least as gate jobs).
Status quo: We have API integration tests for core in the mediawiki/tools/api-testing repo. We also have a CI setup in that repo.
To do:
* create a jenkins job for MW core, similar to the one we run on the mediawiki/tools/api-testing repo.
* that job needs to clone the api-testing repo to a known location, as well as MediaWiki with all the extensions under test.
* we also need to clone the GenerateMochaConfig extension
* instead of running mocha against a single directory as we currently do for mediawiki/tools/api-testing, run it against the config generated by extensions/GenerateMochaConfig/maintenance/generateMochaConfig.php.
* generateMochaConfig.php should get a base config file that includes tests/mocha/ in core as a test target, as well as the test/ directory in api-testing. The script will detect and add any tests/mocha/ directories provided by extensions.
Once all this is up and running, we can move (most) tests from api-testing/test to mediawiki/core/tests/mocha/.