Fix the following error in integration pipeline,
```
=== RUN TestTLSReloadCopy
v3_grpc_test.go:1754: tls: failed to find any PEM data in key input
v3_grpc_test.go:1754: tls: private key does not match public key
v3_grpc_test.go:1754: tls: private key does not match public key
v3_grpc_test.go:1754: tls: private key does not match public key
```
Refer to https://github.com/etcd-io/etcd/runs/7123775361?check_suite_focus=true
Signed-off-by: Benjamin Wang <wachao@vmware.com>
The penalty for TLS is non-trivial with race detection enabled.
Weakening the test certs from 4096-bit RSA to 2048-bit gives ~4x faster
runtimes for TestDoubleTLSClusterSizeOf3.
MacOS base64 uses -D and linux uses -d, while --decode
works on both platforms. And add missing server-ca-csr-wildcard.json.
Signed-off-by: Gyu-Ho Lee <gyuhox@gmail.com>