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
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/28e2c6eacc69e2a186d6fe5d2b9c55c5f978d368

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