pgsql: Use $Test::Builder::Level in TAP test functions

Use $Test::Builder::Level in TAP test functions

In TAP test functions, that is, those that produce test results, locally
increment $Test::Builder::Level. This has the effect that test failures
are reported at the callers location rather than somewhere in the test
support libraries.

Reviewed-by: Heikki Linnakangas <hlinnaka@iki.fi>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c4309f4aeeae54e4c5281d68e29288af1d0d1ed2

Modified Files
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src/bin/pg_rewind/RewindTest.pm | 2 ++
src/test/perl/PostgresNode.pm | 10 ++++++++++
src/test/perl/TestLib.pm | 11 +++++++++++
src/test/ssl/ServerSetup.pm | 4 ++++
4 files changed, 27 insertions(+)