J. David Lowe 115c694af6 etcdserver: don't attempt to grant nil permission to a role
Prevent etcd from crashing when given a bad grant payload, e.g.:

$ curl -d '{"name": "foo"}' http://localhost:2379/v3/auth/role/add
{"header":{"cluster_id":"14841639068965178418", ...
$ curl -d '{"name": "foo"}' http://localhost:2379/v3/auth/role/grant
curl: (52) Empty reply from server
2021-06-04 14:20:02 -07:00
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2021-02-24 19:55:45 +00:00
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