pgsql: meson: Build pgevent as shared_module rather than shared_library

meson: Build pgevent as shared_module rather than shared_library

This matches the behavior of the makefiles and the old MSVC build
system.  The main effect is that the build result gets installed into
pkglibdir rather than bindir.  The documentation says to locate the
library in pkglibdir, so this makes the code match the documentation
again.

Reviewed-by: Ryohei Takahashi (Fujitsu) <r.takahashi_2@fujitsu.com>
Discussion:
https://www.postgresql.org/message-id/flat/TY3PR01MB118912125614599641CA881B782522%40TY3PR01MB11891.jpnprd01.prod.outlook.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/766b0b40aa6a537e8bf899c48736c2ec3ae89869

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