gen by ddl occur panic

[xieyj-apple]

Describe the bug
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To Reproduce
Steps to reproduce the behavior, if applicable:

1. The code is

   CREATE TABLE user (
      id bigint AUTO_INCREMENT,
      dept_id bigint not null DEFAULT 0 COMMENT 'dept id',
      name varchar(255) NULL COMMENT 'The username',
      password varchar(255) NOT NULL DEFAULT '' COMMENT 'The user password',
      mobile varchar(255) NOT NULL DEFAULT '' COMMENT 'The mobile phone number',
      gender char(10) NOT NULL DEFAULT 'male' COMMENT 'gender,male|female|unknown',
      nickname varchar(255) NULL DEFAULT '' COMMENT 'The nickname',
      type tinyint(1) NULL DEFAULT 0 COMMENT 'The user type, 0:normal,1:vip, for test golang keyword',
      create_at timestamp NULL,
      update_at timestamp NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
      UNIQUE mobile_index (mobile),
      UNIQUE dept_name_index (dept, name),
      PRIMARY KEY (id)

) ENGINE = InnoDB COLLATE utf8mb4_general_ci COMMENT 'user table';

2. The error is

panic: runtime error: invalid memory address or nil pointer dereference
[signal 0xc0000005 code=0x0 addr=0x10 pc=0x1b01883]

goroutine 1 [running]:
github.com/zeromicro/go-zero/tools/goctl/model/sql/parser.checkDuplicateUniqueIndex(0xc00064f310?, {0xc000c75480, 0x4})
/github/workspace/tools/goctl/model/sql/parser/parser.go:182 +0x323
github.com/zeromicro/go-zero/tools/goctl/model/sql/parser.Parse({0xc000423080, 0x3e}, {0x0, 0x0}, 0x20?)

**Expected behavior**
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**Screenshots**
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**Environments (please complete the following information):**
- OS: [e.g. Linux]
- go-zero version [e.g. 1.2.1]
- goctl version [e.g. 1.2.1, optional]

**More description**
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[kesonan]

What version of goctl are you using? There will be no panic on my side, only index errors, and this error is the columns you declared on unique index dept_name_index are mismatched, pls upgrade goctl to the latest version and try again.