[BUG] 使用自签名证书服务端启动失败

[Peter]

Trojan Version
v0.10.6

Describe the bug
使用自签名证书启动服务端失败

To Reproduce
Steps to reproduce the behavior:
Step1 使用自签名证书（生成方法如下）
openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -sha256 -days 365
Step2 设置秘钥文件权限 777

-rwxrwxrwx 1 root root 2061 Jul  8 23:19 cert.pem                                                                           
-rwxrwxrwx 1 root root 3394 Jul  8 23:19 key.pem

Step3 配置config

    "ssl": {
        "cert": "**/cert.pem",
        "key": "**/key.pem",
        "key_pssword": "生成秘钥时用的密码",
        "fallback_port": 10086
    }

Step4 启动
./trojan-go -config ../config/config.json

Step5 执行结果 ： 服务启动失败
[FATAL] 2023/07/08 23:23:48 github.com/p4gefau1t/trojan-go/proxy.(*Node).BuildNext:stack.go:29 tls failed to load key pair

Expected behavior
正常启动

Logs
[FATAL] 2023/07/08 23:23:48 github.com/p4gefau1t/trojan-go/proxy.(*Node).BuildNext:stack.go:29 tls failed to load key pair

Environment
centos7

Additional context
none