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_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/0660f74e861d0dc942af3e0b5f88cb2f0c72aee5

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