pgsql: pg_plan_advice: Add CHECK_FOR_INTERRUPTS() and check_stack_depth

pg_plan_advice: Add CHECK_FOR_INTERRUPTS() and check_stack_depth()

Without CHECK_FOR_INTERRUPTS(), backends might not respond to query
cancellations in a timely fashion, especially for JOIN_ORDER()
specifications, where matching against each join can take O(n^2) time
in the length of the join order list in degenerate cases.

Recursive functions should check_stack_depth().

Reported-by: Noah Misch <noah(at)leadboat(dot)com>
Discussion: https://postgr.es/m/CA+TgmoYmXy-jiP5qDhqNEiYFEBzQsArO6O2d9E8szNZqi1bePQ@mail.gmail.com
Backpatch-through: 19

Branch
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REL_19_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ddee5d03077c05925e83533e50ebe805c934d2cf

Modified Files
--------------
contrib/pg_plan_advice/pgpa_ast.c | 14 ++++++++++++++
contrib/pg_plan_advice/pgpa_planner.c | 7 +++++++
contrib/pg_plan_advice/pgpa_trove.c | 3 +++
3 files changed, 24 insertions(+)