[pg] Segfault on select * from pg_type

[rekby]

Reproduce:

1. Run local ydb
2. echo "select * from pg_type" | psql postgres://root:1234@localhost:5432/local

stacktrace

[vitstn]

yqlrun behaviour: Fatal: ERROR: invalid cache ID: 42

crash should be fixed in the ydbd itself

[vitstn]

#2545