pgsql: doc: clarify when expression indexes evaluate their expressions

doc: clarify when expression indexes evaluate their expressions

Only non-HOT updates evaluate the index expression.

Reported-by: Chris Lowder

Discussion: /messages/by-id/163967385701.26064.15365003480975321072@wrigleys.postgresql.org

Backpatch-through: 10

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/2ff209953e0a7b4ce9df1c1ba15783345ef5659f

Modified Files
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doc/src/sgml/indices.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)