pgsql: Be more wary in choice of timezone names to test make_timestampt

Be more wary in choice of timezone names to test make_timestamptz with.

America/Metlakatla hasn't been in the IANA database all that long, so
some installations might not have it. It does seem worthwhile to test
with a fractional-minute GMT offset, but we can get that from almost
any pre-1900 date; I chose Europe/Paris, whose LMT offset from Greenwich
should be pretty darn well established.

Also, assuming that Mars/Mons_Olympus will never be in the IANA database
seems less than future-proof, so let's use a more fanciful location for
the bad-zone-name check.

Per complaint from Christoph Berg.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/66b737cd9a72e10df4de1867ae7b675bc48d478c

Modified Files
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src/test/regress/expected/timestamptz.out | 16 +++++-----------
src/test/regress/sql/timestamptz.sql | 7 +++----
2 files changed, 8 insertions(+), 15 deletions(-)