'EXPLAIN PLAN FOR' not worked for apache-pinot-0.9.3-bin.tar.gz

I download `apache-pinot-0.9.3-bin.tar.gz` from [pinot official website](https://pinot.apache.org/download/) and set up a cluster using this [guide,](https://docs.pinot.apache.org/developers/advanced/advanced-pinot-setup) .

My machine OS is `CentOS Linux release 7.4.1708 (Core)`.

My java version is like this:

```
openjdk version "11.0.14" 2022-01-18 LTS
OpenJDK Runtime Environment 18.9 (build 11.0.14+9-LTS)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.14+9-LTS, mixed mode, sharing)
```

I want to check whether sqls use indexes, etc. But I got an error like this:


And from the broker instance log, I only got this log:

```
Caught exception while compiling SQL request 10: EXPLAIN PLAN FOR select count(*) from transcript_benchmark limit 10, class org.apache.calcite.sql.SqlExplain cannot be cast to class org.apache.calcite.sql.SqlSelect (org.apache.calcite.sql.SqlExplain and org.apache.calcite.sql.SqlSelect are in unnamed module of loader 'app')
```
It seems like pinot uses calcite do sql parser, I don't know why it doesn't work. Could you help me?

Start with the broker instance log and reproduce the reported `EXPLAIN PLAN FOR select count(*) from transcript_benchmark limit 10` query against the apache-pinot-0.9.3-bin.tar.gz setup. Trace the SQL compilation path around the reported SqlExplain-to-SqlSelect cast; done means the query executes without that exception and returns an explain plan.

Written by the indexing model from the issue text.