pgsql: Add CHECK_FOR_INTERRUPTS() to the repeat() function

Add CHECK_FOR_INTERRUPTS() to the repeat() function

The repeat() function loops for potentially a long time without
ever checking for interrupts. This prevents, for example, a query
cancel from interrupting until the work is all done. Fix by
inserting a CHECK_FOR_INTERRUPTS() into the loop.

Backpatch to all supported versions.

Discussion: https://www.postgresql.org/message-id/flat/8692553c-7fe8-17d9-cbc1-7cddb758f4c6%40joeconway.com

Branch
------
REL_11_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/36758c472ea71dae96f4b495df65490413c79c83

Modified Files
--------------
src/backend/utils/adt/oracle_compat.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)