Fix some memory or file descriptor leaks in test code.

[iphydf]

This change is 

[sudden6]

Reviewed 5 of 7 files at r1.
Review status: 5 of 7 files reviewed at latest revision, 3 unresolved discussions.

---

auto_tests/onion_test.c, line 306 at r1 (raw file):

    if (!on->onion) {
        free(on);
        return NULL;

leaks dht and maybe neworking

---

auto_tests/onion_test.c, line 314 at r1 (raw file):

        kill_onion(on->onion);
        free(on);
        return NULL;

same

---

auto_tests/onion_test.c, line 324 at r1 (raw file):

        kill_onion(on->onion);
        free(on);
        return NULL;

same

---

Comments from Reviewable

[iphydf]

Review status: 5 of 7 files reviewed at latest revision, 3 unresolved discussions.

---

auto_tests/onion_test.c, line 306 at r1 (raw file):

Previously, sudden6 wrote…

leaks dht and maybe neworking

Yes, and yes. Fixed both.

---

auto_tests/onion_test.c, line 314 at r1 (raw file):

Previously, sudden6 wrote…

same

Done.

---

auto_tests/onion_test.c, line 324 at r1 (raw file):

Previously, sudden6 wrote…

same

Done.

---

Comments from Reviewable

[Diadlo]

I'm not sure, but what about goto fail; in every if? And place last if body after return on;

[jhert0]

---

Reviewed 6 of 7 files at r1, 1 of 1 files at r2.
Review status: all files reviewed at latest revision, 3 unresolved discussions, some commit checks failed.

---

Comments from Reviewable

[sudden6]

and I also agree with @Diadlo, we should at least consider introducing this style.

---

Reviewed 1 of 7 files at r1, 1 of 1 files at r2.
Review status: all files reviewed at latest revision, all discussions resolved, some commit checks failed.

---

Comments from Reviewable