pgsql: doc: show direction is optional in FETCH/MOVE's FROM/IN syntax

doc: show direction is optional in FETCH/MOVE's FROM/IN syntax

It used to show direction was required for FROM/IN.

Reported-by: Rob <rirans@comcast.net>

Discussion: /messages/by-id/20211015165248.isqjceyilelhnu3k@localhost

Author: Rob <rirans@comcast.net>

Backpatch-through: 10

Branch
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REL_13_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/ccbae5fd8d3b23182ce208df4b3fd018db385e69

Modified Files
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doc/src/sgml/ref/fetch.sgml | 5 +++--
doc/src/sgml/ref/move.sgml | 5 +++--
2 files changed, 6 insertions(+), 4 deletions(-)