pgsql: De-reserve keywords EXECUTE and STRICT in PL/pgSQL.

De-reserve keywords EXECUTE and STRICT in PL/pgSQL.

On close inspection, there does not seem to be a strong reason
why these should be fully-reserved keywords.  I guess they just
escaped consideration in previous attempts to minimize PL/pgSQL's
list of reserved words.

Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Pavel Stehule <pavel.stehule@gmail.com>
Discussion: https://postgr.es/m/2185258.1745617445@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/999f172ded2bae7efbd8bf1dd6f823095395493f

Modified Files
--------------
src/pl/plpgsql/src/expected/plpgsql_misc.out | 14 ++++++++++++++
src/pl/plpgsql/src/pl_gram.y                 | 13 +++++++++----
src/pl/plpgsql/src/pl_reserved_kwlist.h      |  2 --
src/pl/plpgsql/src/pl_scanner.c              |  2 +-
src/pl/plpgsql/src/pl_unreserved_kwlist.h    |  2 ++
src/pl/plpgsql/src/sql/plpgsql_misc.sql      | 13 +++++++++++++
6 files changed, 39 insertions(+), 7 deletions(-)