pgsql: pg_upgrade: Parallelize data type checks.

pg_upgrade: Parallelize data type checks.

This commit makes use of the new task framework in pg_upgrade to
parallelize the checks for incompatible data types, i.e., data
types whose on-disk format has changed, data types that have been
removed, etc. This step will now process multiple databases
concurrently when pg_upgrade's --jobs option is provided a value
greater than 1.

Reviewed-by: Daniel Gustafsson, Ilya Gladyshev
Discussion: https://postgr.es/m/20240516211638.GA1688936%40nathanxps13

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bbf83cab98f2c018d6d394decaa9b03212f96983

Modified Files
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src/bin/pg_upgrade/check.c | 351 ++++++++++++++++++++++++---------------------
1 file changed, 191 insertions(+), 160 deletions(-)