LuaJIT tests are disabled in the scope of the issue [1].

[1] https://github.com/tarantool/tarantool/issues/4819

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In order to support parallel cmake build in the `test-jepsen` target
we need to run Jepsen testing in a `debian-buster` container instead
of `debian-stretch` due to the old `cmake` version in it. The `cmake`
utility started to support `--parallel` option since 3.12 version [1].

In Debian Stretch `cmake` has version 3.7.
In Debian Buster `cmake` has version 3.13.

[1] https://cmake.org/cmake/help/latest/release/3.12.html#command-line

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This patch introduces the new test makefile `.test.mk` instead of the
ancient `.travis.mk`. The `.test.mk` file is a fully reworked version of
`.travis.mk` with the huge refactoring and contains only those targets
that are indeed used.

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