pgsql: Remove redundant spaces in _outA_Expr() output

Remove redundant spaces in _outA_Expr() output

Since WRITE_NODE_FIELD() output always starts with a space, we don't
need to go out of our way to print another space right before it.

This change is only for visual appearance; the tokenizer on the
reading side would read it the same way (but there is no read support
for A_Expr at this time anyway).

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/1c5818b9c68e5c2ac8f19d372f24cce409de1a26

Modified Files
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src/backend/nodes/outfuncs.c | 29 +++++++++++++----------------
1 file changed, 13 insertions(+), 16 deletions(-)