[Tests] Re-enable WITHOUT_CURL tests

[PeterDaveHello]

To prevent #1487 bug appears again.

[PeterDaveHello]

wow the CI time seems to be doubled ... maybe we should test it another way, it's a little bit sad to see the time been doubled after i tried to reduce the time to half twice 😞

[PeterDaveHello]

The problem should be at every tests with TEST_SUITE=installation_node WITHOUT_CURL=1, it's strange that it seems to be not cached, 8 times slower vs TEST_SUITE=installation_node, @ljharb do you have any idea?

[PeterDaveHello]

Though I think it's nothing to do with nodejs itself, I still manually build nodejs v7.8.0 with/without curl, there is no time difference -

with curl:

real    4m20.452s
user    58m27.240s
sys     2m52.876s

without curl:

real    4m19.725s
user    58m26.844s
sys     2m52.728s

[PeterDaveHello]

Okay, got the problem, it's not cached, PR sent #1496

[ljharb]

It might be worth experimenting with the timing of the actual removal of curl - not sure tho, that seems weird.

[PeterDaveHello]

@ljharb nope, the removal takes few secs only, I'm still digging ... #1496 may not fix it.

[PeterDaveHello]

can't figure it out, maybe just see it it'll be fixed by its self ...