test-http-bad-server: move on test from bytes-count to pattern This specific test case is now using the new "close when a pattern is seen" approach compared to the more fragile "that many bytes were sent" approach. Since such change are still a bit noisy, we split each change in there own changesets. Differential Revision: https://phab.mercurial-scm.org/D12050

test-bad-http-server: introduce sock closing when writing a pattern Instead of using a fixed number a bytes, a very unstable method. We introduce a new config that can define a regex. One this regex is detected, nothing after it will be written and the socket will be closed. Tests will be migrated to this new method in later changesets. Differential Revision: https://phab.mercurial-scm.org/D12049

test-http-bad-server: document that the value are actually a list I don't really expect this doc to be read a lot, but mentioning that this is a list seems important. Differential Revision: https://phab.mercurial-scm.org/D12048