tests/gcoap_fileserver: re-enable test on CI

[benpicco]

Contribution description

The GCoAP Fileserver test is actually a large scale integration test of

• IPv6 routing
• 6LoWPAN
• GCoAP server
• nanoCoAP client
• filesystem

So it is quite valuable to have this in CI.

Unfortunately in the past this has proved to be very flaky. Now that the socket_zep fixes are in, maybe this is more stable :crossed_fingers:

Testing procedure

IIUC this should be executed by a normal Murdock run.

Issues/PRs references

[riot-ci]

Murdock results

:x: FAILED

19d94762c3a16716d48a03152c9638757d253f27 tests/gcoap_fileserver: re-enable test on CI

Success	Failures	Total	Runtime
20	0	22	01m:39s

Artifacts

[benpicco]

So much for that :confused:

[crasbe]

If you want to fix this, you could include the changes of #21854. I didn't want to do that in that PR because the test already didn't work and I didn't want to potentially break it more if I can't test it.