pgsql: arrays: tighten checks for multi-dimensional input

arrays:  tighten checks for multi-dimensional input

Previously an input array string that started with a single-element
array dimension would then later accept a multi-dimensional segment.

BACKWARD INCOMPATIBILITY

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/d0ee93797d9c06e619b3f382705d99ee195bb573

Modified Files
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src/backend/utils/adt/arrayfuncs.c   |    8 ++++----
src/test/regress/expected/arrays.out |    2 +-
src/test/regress/sql/arrays.sql      |    2 +-
3 files changed, 6 insertions(+), 6 deletions(-)