pgsql: pg_upgrade check for Unicode-dependent relations.

pg_upgrade check for Unicode-dependent relations.

This check will not cause an upgrade failure, only a warning.

Discussion: https://postgr.es/m/ef03d678b39a64392f4b12e0f59d1495c740969e.camel%40j-davis.com
Reviewed-by: Peter Eisentraut <peter@eisentraut.org>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b81ffa13e35693af8accf00f1694bbeca6809fb6

Modified Files
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src/bin/pg_upgrade/check.c | 180 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 180 insertions(+)