pgsql: Move security_label test

Move security_label test

Rather than have the core security_label regression test depend on the
dummy_seclabel module, have that part of the test be executed by
dummy_seclabel itself directly.  This simplifies the testing rig a bit;
in particular it should silence the problems from the MSVC buildfarm
phylum, which haven't yet gotten taught how to install src/test/modules.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/df761e3cf79db09d602610ee61e51cb378288382

Modified Files
--------------
src/test/modules/dummy_seclabel/Makefile           |    2 +
.../dummy_seclabel/input/dummy_seclabel.source     |   79 +++++++++++++
.../dummy_seclabel/output/dummy_seclabel.source    |   87 ++++++++++++++
src/test/regress/GNUmakefile                       |   16 +--
src/test/regress/expected/security_label.out       |   47 ++++++++
src/test/regress/input/security_label.source       |  108 -----------------
src/test/regress/output/security_label.source      |  123 --------------------
src/test/regress/sql/security_label.sql            |   49 ++++++++
8 files changed, 268 insertions(+), 243 deletions(-)