pgsql: Raise fixed token-length limit in hba.c.

Raise fixed token-length limit in hba.c.

Historically, hba.c limited tokens in the authentication configuration
files (pg_hba.conf and pg_ident.conf) to less than 256 bytes. We have
seen a few reports of this limit causing problems; notably, for
moderately-complex LDAP configurations. Increase the limit to 10240
bytes as a low-risk stop-gap solution.

In v13 and earlier, this also requires raising MAX_LINE, the limit
on overall line length. I'm hesitant to make this code consume
too much stack space, so I only raised that to 20480 bytes.

Discussion: https://postgr.es/m/1588937.1690221208@sss.pgh.pa.us

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/288b4288c3db3af24404cf6d4c1d9d5a9c9c1922

Modified Files
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src/backend/libpq/hba.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)