[venus-auth] Invalid connection and unexpected EOF issues occur / 出现 invalid connection 及 unexpected EOF

### 链服务模块 / Chain Service Components

- [ ] venus
- [X] venus-auth
- [ ] venus-gateway
- [ ] venus-messager
- [ ] venus-miner
- [ ] 文档 / docs

### 订单服务模块 / Deal Service Components

- [ ] venus-market
- [ ] 文档 / docs

### 算力服务模块 / Storage Power Service Components

- [ ] venus-sector-manager
- [ ] venus-worker
- [ ] 文档 / docs

### 描述 / Description

遇到 invalid connection 及 unexpected EOF

```
[260.821ms] [rows:1] SELECT count(*) FROM `signers` WHERE `signer` = '3tfser6vgjw5fhb3i4tmjpauiqurcykhmqy2myzbc67lar72tluf7qkjctlon6ys7m5w4kc4znzcqooi6cska' AND `user` = 'cq-21' AND deleted_at IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: read tcp 10.123.1.235:41534->47.103.182.80:3306: i/o timeout
[mysql] 2023/05/19 19:31:49 packets.go:37: read tcp 10.123.1.235:41732->47.103.182.80:3306: i/o timeout

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120009.404ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3qyd2itgmzujn4sqsm7lc2muvvnq7yzotxlc7jpqlonjwetnupjii5bxx6jr2ijodyqvdtgczglewskb4mnna' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120009.638ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3q3gcskttwevlkzxdu4zox7in7cn7wl7x7bbr7bboqtz7ubouxrymh3u5mf6meg666s5revpsn5frnit3ic3q' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120009.651ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3rmk4y65ju7rngezeezotup2i7ouu6mssjlmkrhbm64tmaqog6m6ozkes3vrmu56vytuniy4r2hvud6x34tra' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120007.053ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3r6m4tkjavy7a5gtyudah3oes3sratlq6g4gwgdee2jtrirsibcayhnd55czr5ig6l7jg3z36cwh6pq5qngaa' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120006.872ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3shss47rcdmkm76fgl5r6vlthwupryffj2fkfmv2po6fqyxogoqmv3ua263w2najchlvusvlddp3hsc5mg52a' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120007.393ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3r4vi7zl2oxk4gk34x3lnq7kpr6mlxnpgbiorclplhvk5xill5tkojbpnwitc7opwvmukryi3nmoh76fekrka' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120007.655ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3sqrjmmwyffqw4x6ao5r4ynbwsatj6x3hy22ilvi625piw6cx7ovhwacpedathodcy6fz6jqpkwztqcoj47la' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF
[mysql] 2023/05/19 19:31:49 packets.go:37: unexpected EOF

2023/05/19 19:31:49 /home/runner/work/venus-auth/venus-auth/storage/mysql.go:434 invalid connection; invalid connection
[120007.709ms] [rows:-] SELECT users.* FROM `signers` inner join users on signers.`signer` = '3qrre5lkrwtstguhjytqmiphhtnhnioxuujnilrvrli2hzi4guk2crcsejdmdutdk3mhgamyc2u62vrcm742q' and users.`name` = signers.`user` and users.`is_deleted` = 0 WHERE `signers`.`deleted_at` IS NULL
```

[详细日志](https://github.com/filecoin-project/venus/files/11538654/venus-auth-connect-mysql.log)