Added some hooks for DROP TABLE

[Hydrocharged]

This adds support for ensuring that dropping a table while using table types doesn't outright put the database in an unusable state. There are many more hooks that need to be implemented across the board, but these are relatively straightforward ones for a common case of dropping a table, function, or procedure that uses them.

This also adds support for DROP PROCEDURE, which I apparently overlooked when adding procedure support in general. Lastly, this adds support for the serialization and deserialization of values within columns that use table types. While it was previously possible to create tables that use table types, it wasn't possible to read from those tables (and writing to them just wrote useless data that couldn't be removed).

You'll notice that error messages involving procedures return "function" instead of "procedure". Postgres calls them functions in their error messages, so we're replicating that.

[github-actions]

	Main	PR
covering_index_scan_postgres	570.94/s	558.72/s	-2.2%
index_join_postgres	119.51/s	118.47/s	-0.9%
index_join_scan_postgres	180.82/s	178.73/s	-1.2%
index_scan_postgres	11.35/s	11.26/s	-0.8%
oltp_point_select	2286.83/s	2281.73/s	-0.3%
oltp_read_only	1709.91/s	1697.47/s	-0.8%
select_random_points	105.26/s	105.53/s	+0.2%
select_random_ranges	431.09/s	414.43/s	-3.9%
table_scan_postgres	11.07/s	11.38/s	+2.8%
types_table_scan_postgres	5.09/s	5.16/s	+1.3%

[github-actions]

	Main	PR
Total	42090	42090
Successful	17304	17314
Failures	24786	24776
Partial Successes1	5596	5595

	Main	PR
Successful	41.1119%	41.1357%
Failures	58.8881%	58.8643%

${\color{lightgreen}Progressions (10)}$

create_procedure

QUERY: CALL ptest2();

QUERY: DROP PROCEDURE ptest4a;

QUERY: DROP PROCEDURE ptest2;

drop_if_exists

QUERY: DROP PROCEDURE test_ambiguous_procname(int);

QUERY: DROP PROCEDURE test_ambiguous_procname(text);

enum

QUERY: DROP FUNCTION echo_me(rainbow);

event_trigger

QUERY: call p1();

QUERY: drop table event_trigger_fire2, event_trigger_fire3, event_trigger_fire4, event_trigger_fire5, event_trigger_fire6, event_trigger_fire7;

publication

QUERY: DROP ROLE regress_publication_user, regress_publication_user2;

QUERY: DROP ROLE regress_publication_user_dummy;

Footnotes

1. These are tests that we're marking as Successful, however they do not match the expected output in some way. This is due to small differences, such as different wording on the error messages, or the column names being incorrect while the data itself is correct. ↩

[zachmu]

LGTM