bug: parse_type_desc maybe has some question

[TCeason]

I do an ut test_parse_type_desc on my local: if input is : Nullable(Tuple(String NULL, Array(Tuple(Array(Int32 NULL) NULL, Array(String NULL) NULL) NULL) NULL))

the output of parse_type_desc is :

  left: `TypeDesc { name: "Nullable", args: [TypeDesc { name: "Tuple", args: [TypeDesc { name: "NULL", args: [TypeDesc { name: "String", args: [] }] }, TypeDesc { name: "NULL", args: [TypeDesc { name: "NULL", args: [TypeDesc { name: "NULL", args: [TypeDesc { name: "NULL", args: [TypeDesc { name: "Int32", args: [] }] }] }, TypeDesc { name: "NULL", args: [TypeDesc { name: "NULL", args: [TypeDesc { name: "String", args: [] }] }] }] }] }] }] }`,

We can see that the Array type is dropped.

[TCeason]

cc @everpcpc