QA: plainto_tsquery can't parse !!, &&, ||, <->, etc.

[msirek]

Postgres ignores non-alphanumeric symbols in the argument to plainto_tsquery, but CRDB does not,
e.g.

postgres=# select plainto_tsquery('fat !! bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

postgres=# select plainto_tsquery('fat &&& bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

postgres=# select plainto_tsquery('fat ) bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

postgres=# select plainto_tsquery('fat && bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

postgres=# select plainto_tsquery('fat || bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

postgres=# select plainto_tsquery('fat <-> bat');
 plainto_tsquery 
-----------------
 'fat' & 'bat'
(1 row)

All of these examples return a syntax error on CRDB, e.g.

root@localhost:26257/defaultdb> select plainto_tsquery('fat <-> bat');                                                                                                                            
ERROR: plainto_tsquery(): syntax error in TSQuery: fat <-> bat
SQLSTATE: 42601

Jira issue: CRDB-25956