pgsql: Improve PDF documentation margins

Improve PDF documentation margins

Set body indent to 0 to make use of the horizontal space better (and
some reviewers thought it was also more readable).

Add some left and right margin to the warning boxes, otherwise they
drift too far off the page in combination with the above change.

Author: Noboru Saito <noborusai(at)gmail(dot)com>
Reviewed-by: Hayato Kuroda (Fujitsu) <kuroda(dot)hayato(at)fujitsu(dot)com>
Reviewed-by: Florents Tselai <florents(dot)tselai(at)gmail(dot)com>
Reviewed-by: Tatsuo Ishii <ishii(at)postgresql(dot)org>
Discussion: https://www.postgresql.org/message-id/flat/CAAM3qnLyMUD79XF+SqAVwWCwURCF3hyuFY9Ki9Csbqs-zMwwnw(at)mail(dot)gmail(dot)com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/37e06ba6e82b44fc6ebfc9e52d71f0c21d0044c4

Modified Files
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doc/src/sgml/stylesheet-fo.xsl | 4 ++++
1 file changed, 4 insertions(+)