Add diagnostic for for-in loop · Pull Request !6939 · OpenHarmony/arkcompiler_ets_frontend

### **Issue**

https://gitee.com/openharmony/arkcompiler_ets_frontend/issues/ICLIJR

### **Reason**
arkts-no-for-in

### **Description**

ArkTS doesn't support for ... in ... loops.

Example:

```
let a: number[] = [1.0, 2.0, 3.0]
for (let i in a) {
  console.log(a[i])
}
```

Current error message:

```
SyntaxError: Variable must be initialized or it's type must be declared. [test.sts:2:12]
SyntaxError: Variable must be initialized or it's type must be declared. [test.sts:2:12]
SyntaxError: Unexpected token 'in'. [test.sts:2:12]
```

Suggested error message:
`'for ... in' loop is not supported, please use regular 'for' or 'for ... of ...' loop to iterate through arrays and iterable objects.`

Parsing of for ... in loops is already implemented, only ValidateForInStatement() function should be modified to return a more meaningful error message.

### **Tests**
```
ninja all tests
```
**All required pre-merge tests passed. Results are available in the internal CI.**

Fixes #23686 internal issue.
Change-Id: If24fa5e45928a679fd2d718e4c4d602fc1e80441

类型	指派人员	状态
审查	@egavrin 由 CODEOWNERS 文件第 18 行指派为审查者	已完成 (1/1人)
审查	godmiaozi zhuoli72 gavin1012_hw 徐城 Ilya Trubachev Urakov Alexandr Chernykh Sergey 已审查通过 Vsevolod Pukhov 已审查通过	已完成 (2/1人)
测试	openharmony_ci 已测试通过	已完成 (1/1人)

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