pgsql: Add more test coverage for jsonpath "$.*" with arrays

Add more test coverage for jsonpath "$.*" with arrays

There was no coverage for the code path to unwrap an array before
applying ".*" to it, so add tests to provide more coverage for both
objects and arrays.

This shows, for example, that no results are returned for an array of
scalars, and what results are returned when the array contains an
object. A few more scenarios are covered with the strict/lax modes and
the operator "@?".

Author: David Wheeler
Reported-by: David G. Johnston, Stepan Neretin
Discussion: https://postgr.es/m/A95346F9-6147-46E0-809E-532A485D71D6@justatheory.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3a137ab7e575b683c410c46312799a4d88e2b2f2

Modified Files
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src/test/regress/expected/jsonb_jsonpath.out | 50 ++++++++++++++++++++++++++++
src/test/regress/sql/jsonb_jsonpath.sql | 11 ++++++
2 files changed, 61 insertions(+)