panic when creating sink into a table which is created by CREATE TABLE AS

[st1page]

dev=> create table t as select 1;
INSERT 0 1
dev=> create sink s into t as select 2 as v with (type = 'append-only');
ERROR:  Panicked when handling the request: called `Result::unwrap()` on an `Err` value: []
This is a bug. We would appreciate a bug report at:
  https://github.com/risingwavelabs/risingwave/issues/new?labels=type%2Fbug&template=bug_report.yml
server closed the connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
The connection to the server was lost. Attempting reset: Succeeded.

thread 'rw-main' panicked at src/frontend/src/handler/create_sink.rs:561:10:
called `Result::unwrap()` on an `Err` value: []
stack backtrace:
   0: rust_begin_unwind
             at /rustc/e4c626dd9a17a23270bf8e7158e59cf2b9c04840/library/std/src/panicking.rs:645:5
   1: core::panicking::panic_fmt
             at /rustc/e4c626dd9a17a23270bf8e7158e59cf2b9c04840/library/core/src/panicking.rs:72:14
   2: core::result::unwrap_failed
             at /rustc/e4c626dd9a17a23270bf8e7158e59cf2b9c04840/library/core/src/result.rs:1649:5
   3: core::result::Result<T,E>::unwrap
             at /rustc/e4c626dd9a17a23270bf8e7158e59cf2b9c04840/library/core/src/result.rs:1073:23
   4: risingwave_frontend::handler::create_sink::reparse_table_for_sink::{{closure}}
             at ./src/frontend/src/handler/create_sink.rs:558:32
   5: risingwave_frontend::handler::create_sink::handle_create_sink::{{closure}}
             at ./src/frontend/src/handler/create_sink.rs:443:62

It is because the definition is None for the CREATE TABLE AS

dev=> show create table t;
   Name   | Create Sql 
----------+------------
 public.t | 
(1 row)

[fuyufjh]

If we have already heavily relied on the CREATE TABLE statement, it seems like we need to build such a CREATE TABLE (<column_definitions>) for CREATE TABLE AS