[I] Placeholder datatype not inferred after `LIMIT` clause [datafusion]

[via GitHub]

kczimm opened a new issue, #15978:
URL: https://github.com/apache/datafusion/issues/15978

   ### 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_


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