pgsql: Forbid FOR PORTION OF on views with INSTEAD OF triggers

Forbid FOR PORTION OF on views with INSTEAD OF triggers

Previously, an attempt to use these features together caused a crash.
Oversight of commit 8e72d914c528.

Tests are added also to show that the check for this should be in the
rewriter, not the parser, as an earlier patch version suggested.

Author: Aleksander Alekseev <aleksander(at)tigerdata(dot)com>
Author: Paul A. Jungwirth <pj(at)illuminatedcomputing(dot)com>
Discussion: https://www.postgresql.org/message-id/flat/CAJ7c6TME%2Bix6VRf-2TPnVTsj8qn_hy6sYAOmMhZEivwsu2wS6g%40mail.gmail.com

Branch
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REL_19_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5b5e99047ab0df2ef3d18de81176558e49015205

Modified Files
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src/backend/rewrite/rewriteHandler.c | 8 +++
src/test/regress/expected/updatable_views.out | 71 ++++++++++++++++++++++++++
src/test/regress/sql/updatable_views.sql | 73 +++++++++++++++++++++++++++
3 files changed, 152 insertions(+)