letsencrypt脚本出现了错误：letsencrypt.sh: line 50: syntax error near unexpected token `('

```bash
[root@canbin-aliyun www]# sh /www/letsencrypt.sh /www/letsencrypt.conf
Generate CSR...94cb.csr
/www/letsencrypt.sh: line 50: syntax error near unexpected token `('
/www/letsencrypt.sh: line 50: `openssl req -new -sha256 -key "$DOMAIN_KEY" -subj "/" -reqexts SAN -config <(cat $OPENSSL_CONF <(printf "[SAN]\nsubjectAltName=%s" "$DOMAINS")) > "$DOMAIN_CSR"'
```