pgsql: Show plperl version in the meson setup summary.

Show plperl version in the meson setup summary.

Also, use perl 'version' instead of 'api_versionstring' to sync with
the configure script.

Author: Roman Zharkov <r.zharkov@postgrespro.ru>

Discussion: /messages/by-id/93e7f77bf4e1ef4640e4ee733f9e2a78@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/12604593e9f3b3460f7359a39d25731aff6beb88

Modified Files
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meson.build | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)