Bug: The scope of the attribute inside the schema is incorrect

[zong-zhe]

Bug Report

Please answer these questions before submitting your issue. Thanks!

1. Minimal reproduce step (Required)

The main.k:

schema Fold:
    l: [any]
    acc: any
    func: (any, any) -> any
    value: any = acc if len(l) == 0 else Fold {
        # `l` has been replaced by `l[1::]`. When the size of `l` is 1, the next line should raise an error
        l: l[1::] 
        # the `l` has been replaced in the previous line, when the size of `l` is 1, error here !
        acc: func(acc, l[0])
        func: func
    }.value

flod = Fold {
    l: [1, 2, 3, 4, 5],
    acc: 0,
    func: lambda x, y { x + y }
}.value

2. What did you expect to see? (Required)

An error raised.

3. What did you see instead (Required)

No errors, and an result got:

flod: 15

4. What is your KCL components version? (Required)

The main branch of KCL