tests: avoid false fails on NFS due to EPERM

tests: avoid false fails on NFS due to EPERM

* tests/chgrp/basic.sh: On some NFS setups a user is
not allowed to set a group on a file even if a member
of that group.  Therefore skip this test on remote file systems.
* tests/chgrp/default-no-deref.sh: Likewise.
* tests/chgrp/no-x.sh: Likewise.
* tests/chgrp/posix-H.sh: Likewise.
* tests/chgrp/recurse.sh: Likewise.
* tests/tail-2/inotify-rotate-resources.sh: Change to skipping
on remote file systems in the standard way.