Placeholder datatype not inferred after `LIMIT` clause

### Describe the bug

When using a parameterized query with a placeholder indicating the value in the `LIMIT` clause, the datatype is not inferred.

### To Reproduce

```rust
let schema = Arc::new(Schema::new(vec![Field::new("A", DataType::Int32, true)]));
let source = Arc::new(LogicalTableSource::new(schema.clone()));

let placeholder_value = "$1";

// SELECT * FROM my_table LIMIT $1
let plan = LogicalPlan::Limit(Limit {
skip: None,
fetch: Some(Box::new(Expr::Placeholder(Placeholder {
id: placeholder_value.to_string(),
data_type: None,
}))),
input: Arc::new(LogicalPlan::TableScan(TableScan {
table_name: TableReference::from("my_table"),
source,
projected_schema: Arc::new(DFSchema::try_from(schema.clone())?),
projection: None,
filters: vec![],
fetch: None,
})),
});

let params = plan.get_parameter_types().expect("to infer type");
assert_eq!(params.len(), 1);

let parameter_type = params
.clone()
.get(placeholder_value)
.expect("to get type")
.clone();
assert_eq!(parameter_type, Some(DataType::Int64));
```

```shell
assertion `left == right` failed
left: None
right: Some(Int64)
```

### Expected behavior

Assertion passes.

### Additional context

_No response_

Start at LogicalPlan::Limit and Expr::Placeholder, then trace get_parameter_types() for the LIMIT fetch expression. Reproduce the issue with the Rust example in the report and verify that the placeholder map contains Some(DataType::Int64), so the assertion passes.

Written by the indexing model from the issue text.