Enable SA gRPC health checks in Consul ahead of further changes for
#6878. Calls to the `Check` method of the SA's grpc.health.v1.Health
service must respond `SERVING` before the `sa` service will be
advertised in Consul DNS. Consul will continue to poll this service
every 5 seconds.
- Add `bconsul` docker service to boulder `bluenet` and `rednet`
- Add TLS credentials for `consul.boulder`:
```shell
$ openssl x509 -in consul.boulder/cert.pem -text | grep DNS
DNS:consul.boulder
```
- Update `test/grpc-creds/generate.sh` to add `consul.boulder`
- Update test SA configs to allow `consul.boulder` to access to
`grpc.health.v1.Health`
Part of #6878
f09a94bd74