pgsql: Disable installcheck tests for test_session_hooks

Disable installcheck tests for test_session_hooks

The module requires a preloaded library and the defect can't be cured by
a LOAD instruction in the test script. To achieve this we override the
installcheck target in the module's Makefile, and exclude ithe module in
vcregress.pl.

Along the way, revert commit 9989f92aabd.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/745948422c799c1b9f976ee30f21a7aac050e0f3

Modified Files
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src/test/modules/Makefile                    | 1 +
src/test/modules/test_session_hooks/Makefile | 4 ++++
src/tools/msvc/vcregress.pl                  | 2 ++
3 files changed, 7 insertions(+)