[PATCH v2] stdlib/tst-secure-getenv: handle >64 groups

[Florian Weimer]

* Mike Gerow:

> This test would fail unnecessarily if the user running it had more than
> 64 groups since getgroups returns EINVAL if the size provided is less
> than the number of supplementary group IDs. Instead dynamically
> determine the number of supplementary groups the user has.

Looks good.  Do you have commit access?  If not, I can add a ChangeLog
entry and push this on your behalf.

Thanks,
Florian