Run some open-source projects through an aggressive debug
configuration with asan and ubsan. We don't care about test results,
only check that we don't assert or crash.
Currently testing laravel, symfony and amp.
This uses a separate job template, because msan requires all used
libraries (apart from glibc) to be instrumented, so we can't link
any external libraries unless we recompile them. As such, we need
a much more minimal configure.
Also adds an --asan flag to run-tests.php to setup all the necessary
environment variables. Some tests are marked as skipped because they
are incompatible with asan or too slow.
I'm basing this on the DEBUG_ZTS build, which seems to give us the
most mileage.
