pgsql: Mark internal messages as no longer translatable

Mark internal messages as no longer translatable

The problem that these messages protect against can only occur because
a corrupted hash spill file was written, i.e., a Postgres bug.  There's
no reason to have them as translatable.

Backpatch to 15, where these messages were changed by commit c4649cce39a4.

Reviewed-by: Daniel Gustafsson <daniel@yesql.se>
Discussion: https://postgr.es/m/20230510175407.dwa5v477pw62ikyx@alvherre.pgsql

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f06156da18f67bc2c904c0a76b70dafcb14ca7c2

Modified Files
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src/backend/executor/nodeAgg.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)