The previous version of full_test_suite.py directly called the test
binary, which was being compiled at the same time as the static library.
However, by passing the --tests argument to cargo, rustc was ignoring
several important release-profile configurations, and was also
attempting to link the test binary, which was breaking cross-compilation
builds.
This commit alters src/Makefile.am to only build the static library, and
leaves test compilation to the test runner itself. This ensures that the
tests are only compiled for native builds, when the tests will be run on
the same platform.
Not moved, because upstream makes improvements to this script, and the need to
set environment variables makes it simpler to just use the given script.