pgsql: Add test for REPLICA IDENTITY with a temporal key

Add test for REPLICA IDENTITY with a temporal key

You can only use REPLICA IDENTITY USING INDEX with a unique B-tree
index.  This commit just adds a test showing that you cannot use it
with a WITHOUT OVERLAPS index (which is GiST).

Author: Paul A. Jungwirth <pj@illuminatedcomputing.com>
Discussion: https://www.postgresql.org/message-id/3775839b-3f0f-4c8a-ac03-a253222e6a4b%40illuminatedcomputing.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/482e108cd38db5366c52a6b1f4180f34c1796155

Modified Files
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src/test/regress/expected/without_overlaps.out | 4 ++++
src/test/regress/sql/without_overlaps.sql      | 4 ++++
2 files changed, 8 insertions(+)