test: rename 'check-code' own test to 'test-contrib-check-code.t'...
test: rename 'check-code' own test to 'test-contrib-check-code.t'
This test (making sure the 'check-code' script run as intended) have been
confused with the test making that the mercurial code base comply with our
coding still by multiple generations of contributors.
We are moving it out of the way so that all tests starting with
'test-check' are now doing compliance testing.
