Обсуждение: pgsql: Add regression test coverage for timetz_izone().

Add regression test coverage for timetz_izone().

Extend the test added by commit 97957fdba so that it also covers
timetz_izone(), that is the "AT TIME ZONE interval" case.
This is mostly to see if xlc's apparent bug occurs there too,
but more code coverage is always welcome.

Discussion: https://postgr.es/m/2287835.1697464481@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2f047203074c643ae458dcf51bbb8ae45dd7e13c

Modified Files
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src/test/regress/expected/timetz.out | 51 ++++++++++++++++++------------------
src/test/regress/sql/timetz.sql      |  8 +++---
2 files changed, 30 insertions(+), 29 deletions(-)