Re: PGQ catalog representation and pg_dump support

As I was looking more into dependency related parts of GRAPH,
I encountered this, which I don't see mentioned in this thread already.

```
postgres=# CREATE TABLE t_alter_type (
id int PRIMARY KEY,
payload int
);

CREATE PROPERTY GRAPH g_alter_type
VERTEX TABLES (
t_alter_type PROPERTIES (payload AS payload_prop)
);

ALTER TABLE t_alter_type ALTER COLUMN payload TYPE bigint;
CREATE TABLE
CREATE PROPERTY GRAPH
ERROR: unexpected object depending on column: property payload_prop
of label t_alter_type of vertex t_alter_type of property graph
g_alter_type
postgres=#
```

ISTM that RememberAllDependentForRebuilding() does not handle all
property graph cases
properly.

--
Sami Imseih
Amazon Web Services (AWS)