We can't run them in parallel, but we can at least have 'make check'
run them all.
Developers should be running "make check-source && make check".
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
These use the same infrastructure as the daemon/test blackbox tests,
so they're not currently wired into make check; use make
"lightningd-blackbox-tests".
Rusty Russell