pgsql: Add 'tap_tests' flag in config_default.pl

Add 'tap_tests' flag in config_default.pl

This makes the flag more visible for testers using the default file as a
template, increasing the likelyhood that the test suite will be run.
Also have the flag be displayed in the fake "configure" output, if set.

This patch is two new lines only, but perltidy decides to shift things
around which makes it appear a bit bigger.

Author: Michaël Paquier
Reviewed-by: Craig Ringer
Discussion:
https://www.postgresql.org/message-id/CAB7nPqRet6UAP2APhZAZw%3DVhJ6w-Q-gGLdZkrOqFgd2vc9-ZDw%40mail.gmail.com

Branch
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REL9_4_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/c7327561f75717205d0790e8629b5ea676b8b962

Modified Files
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src/tools/msvc/Solution.pm       | 1 +
src/tools/msvc/config_default.pl | 1 +
2 files changed, 2 insertions(+)