pgsql: doc: Fix log_parameter_max_length docs to reference log_min_dura

doc: Fix log_parameter_max_length docs to reference log_min_duration_statement

The documentation for log_parameter_max_length said it affects messages
generated by log_duration. However, log_duration alone does not log bind
parameter values, so this is misleading.

This commit updates the documentation to reference log_min_duration_statement,
which can log bind parameters, to better reflect actual behavior.

Backpatch to all supported versions.

Author: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Reviewed-by: Surya Poondla <suryapoondla4(at)gmail(dot)com>
Discussion: https://postgr.es/m/CAHGQGwGnCVMVz8-LU9F8Sh57bkQX3jMZzx7age7M0LFEz5=Fog@mail.gmail.com
Backpatch-through: 14

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e6e8277f420f3b348ad5e414761196c5d02acb82

Modified Files
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doc/src/sgml/config.sgml | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)