pgsql: Adjust indentation in src/backend/optimizer/README.

Adjust indentation in src/backend/optimizer/README.

The previous indentation of optimizer functions was unclear; adjust the
indentation dashes so that a deeper level of indentation indicates that
the outer optimizer function calls the inner one.

Author: Richard Guo, with additional change by me
Reviewed-by: Kyotaro Horiguchi
Discussion: https://postgr.es/m/CAMbWs4-U-ogzpchGsP2BBMufCss1hktm%2B%2BeTJK_dUC196pw0cQ%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bb2ae6fa47e5d84b6c5a9e3845021e7df031ec32

Modified Files
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src/backend/optimizer/README | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)