pgsql: meson: Improve/fix Python version selection

meson: Improve/fix Python version selection

When we look for the Python installation using the meson python
module, we should make it use the python program previously determined
by the 'PYTHON' option.  Otherwise, it will just use its own search
and the 'PYTHON' option won't affect it.  We need this to be able to
select the Python installation to build PL/Python against.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/3f5427e8-cef6-474d-ae88-13db1bfdc1a7%40eisentraut.org

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/1f5e38847b26265c15bf367de516b46491c3a7c3

Modified Files
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meson.build | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)