add 'FAIL:' to egrep
```shell
[root@LF-136-9 etcd]# egrep "(--- FAIL:|DATA RACE|panic: test timed out|appears to have leaked)" -B50 -A10 test-MTYyNjIyOTc0MQo.log
[root@LF-136-9 etcd]# egrep "(--- FAIL:|FAIL:|DATA RACE|panic: test timed out|appears to have leaked)" -B50 -A10 test-MTYyNjIyOTc0MQo.log
ok go.etcd.io/etcd/server/v3/auth 3.247s
ok go.etcd.io/etcd/server/v3/config 0.047s
ok go.etcd.io/etcd/server/v3/datadir 0.035s
ok go.etcd.io/etcd/server/v3/embed 1.944s
ok go.etcd.io/etcd/server/v3/etcdmain 0.326s
FAIL go.etcd.io/etcd/server/v3/etcdserver [build failed]
? go.etcd.io/etcd/server/v3/etcdserver/api [no test files]
ok go.etcd.io/etcd/server/v3/etcdserver/api/etcdhttp 0.110s
ok go.etcd.io/etcd/server/v3/etcdserver/api/membership 0.479s
ok go.etcd.io/etcd/server/v3/etcdserver/api/rafthttp 0.251s
ok go.etcd.io/etcd/server/v3/etcdserver/api/snap 0.045s
? go.etcd.io/etcd/server/v3/etcdserver/api/snap/snappb [no test files]
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2auth 1.470s
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2discovery 0.088s
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2error 0.034s
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2http 0.128s
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2http/httptypes 0.033s
? go.etcd.io/etcd/server/v3/etcdserver/api/v2stats [no test files]
ok go.etcd.io/etcd/server/v3/etcdserver/api/v2store 0.068s
? go.etcd.io/etcd/server/v3/etcdserver/api/v2v3 [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3alarm [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3client [no test files]
ok go.etcd.io/etcd/server/v3/etcdserver/api/v3compactor 1.793s
? go.etcd.io/etcd/server/v3/etcdserver/api/v3election [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3election/v3electionpb [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3election/v3electionpb/gw [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3lock [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3lock/v3lockpb [no test files]
? go.etcd.io/etcd/server/v3/etcdserver/api/v3lock/v3lockpb/gw [no test files]
ok go.etcd.io/etcd/server/v3/etcdserver/api/v3rpc 0.089s
ok go.etcd.io/etcd/server/v3/etcdserver/cindex 0.045s
ok go.etcd.io/etcd/server/v3/lease 3.324s
ok go.etcd.io/etcd/server/v3/lease/leasehttp 2.096s
? go.etcd.io/etcd/server/v3/lease/leasepb [no test files]
? go.etcd.io/etcd/server/v3/mock/mockstorage [no test files]
? go.etcd.io/etcd/server/v3/mock/mockstore [no test files]
? go.etcd.io/etcd/server/v3/mock/mockwait [no test files]
ok go.etcd.io/etcd/server/v3/mvcc 8.805s
ok go.etcd.io/etcd/server/v3/mvcc/backend 1.983s
? go.etcd.io/etcd/server/v3/mvcc/backend/testing [no test files]
? go.etcd.io/etcd/server/v3/mvcc/buckets [no test files]
? go.etcd.io/etcd/server/v3/proxy/grpcproxy [no test files]
? go.etcd.io/etcd/server/v3/proxy/grpcproxy/adapter [no test files]
? go.etcd.io/etcd/server/v3/proxy/grpcproxy/cache [no test files]
ok go.etcd.io/etcd/server/v3/proxy/httpproxy 0.046s
ok go.etcd.io/etcd/server/v3/proxy/tcpproxy 0.035s
? go.etcd.io/etcd/server/v3/verify [no test files]
ok go.etcd.io/etcd/server/v3/wal 0.513s
ok go.etcd.io/etcd/server/v3/wal/walpb 0.045s
FAIL
FAIL: (code:2):
% (cd server && env go test -short -timeout=3m --race --cpu=16 ./...)
FAIL: 'unit' failed at Wed Jul 14 10:29:37 CST 2021
```
we found a lease leak issue:
if a new member(by member add) is recovered by snapshot, and then
become leader, the lease will never expire afterwards. leader will
log the revoke failure caused by "invalid auth token", since the
token provider is not functional, and drops all generated token
from upper layer, which in this case, is the lease revoking
routine.
When running 100 times in row those tests flaked around 10-20%. Based on
some experimentation 10 keys was enough to ensure that wal snapshot is
created and prevented any flakes.
