pgsql: doc: Use proper tags in pg_overexplain documentation.

pgsql: doc: Use proper tags in pg_overexplain documentation.

doc: Use proper tags in pg_overexplain documentation.

The pg_overexplain documentation previously used the  tag for
some file names, struct names, and commands. Update the markup to
use the more appropriate tags: , , and .

Backpatch to v18, where pg_overexplain was introduced.

Author: Fujii Masao 
Reviewed-by: Shixin Wang 
Reviewed-by: Chao Li 
Discussion: https://postgr.es/m/CAHGQGwEyYUzz0LjBV_fMcdwU3wgmu0NCoT+JJiozPa8DG6eeog@mail.gmail.com
Backpatch-through: 18

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/008beba005c9990e2ba2a729c08585f051a24950

Modified Files
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doc/src/sgml/pgoverexplain.sgml | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)