pgsql: PL/Tcl: Improve trigger tests organization

PL/Tcl: Improve trigger tests organization

The trigger tests for PL/Tcl were spread aroud pltcl_setup.sql and
pltcl_queries.sql, mixed with other tests, which makes them hard to
follow and edit.  Move all the trigger-related pieces to a new file
pltcl_trigger.sql.  This also makes the test setup more similar to
plperl and plpython.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/aefcc2bba211b738b3dd3cb393d9cdfcbcdc83cd

Modified Files
--------------
src/pl/tcl/Makefile                   |   2 +-
src/pl/tcl/expected/pltcl_queries.out | 383 +----------------
src/pl/tcl/expected/pltcl_setup.out   | 425 +-----------------
src/pl/tcl/expected/pltcl_trigger.out | 789 ++++++++++++++++++++++++++++++++++
src/pl/tcl/sql/pltcl_queries.sql      | 123 +-----
src/pl/tcl/sql/pltcl_setup.sql        | 455 +-------------------
src/pl/tcl/sql/pltcl_trigger.sql      | 567 ++++++++++++++++++++++++
7 files changed, 1379 insertions(+), 1365 deletions(-)