pgsql: Adapt appendPsqlMetaConnect() to the new fmtId() encoding expect

Adapt appendPsqlMetaConnect() to the new fmtId() encoding expectations.

We need to tell fmtId() what encoding to assume, but this function
doesn't know that. Fortunately we can fix that without changing the
function's API, because we can just use SQL_ASCII. That's because
database names in connection requests are effectively binary not text:
no encoding-aware processing will happen on them.

This fixes XversionUpgrade failures seen in the buildfarm. The
alternative of having pg_upgrade use setFmtEncoding() is unappetizing,
given that it's connecting to multiple databases that may have
different encodings.

Andres Freund, Noah Misch, Tom Lane

Security: CVE-2025-1094

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5bf12323b6b8b05790aab6876555568898f4fc81

Modified Files
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src/fe_utils/string_utils.c | 19 ++++++++++++++-----
1 file changed, 14 insertions(+), 5 deletions(-)