pgsql: pg_prewarm: Allow autoprewarm to use more than 1GB to dump block

pg_prewarm: Allow autoprewarm to use more than 1GB to dump blocks.

Reported-by: Daria Shanina <vilensipkdm@gmail.com>
Author: Daria Shanina <vilensipkdm@gmail.com>
Author: Robert Haas <robertmhaas@gmail.com>
Backpatch-through: 13

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/a4b9707c417666841733fe4f5bec9b18e184028e

Modified Files
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contrib/pg_prewarm/autoprewarm.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)