pgsql: Add output test for pg_dependencies statistics import

Add output test for pg_dependencies statistics import

Commit 302879bd68d115 has added the ability to restore extended stats of
the type "dependencies", but it has forgotten the addition of a test to
verify that the value restored was actually set.

This test is the pg_dependencies equivalent of the test added for
pg_ndistinct in 0e80f3f88dea.

Author: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://postgr.es/m/CADkLM=dZr_Ut3jKw94_BisyyDtNZPRJWeOALXVzcJz=ZFTAhvQ@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/f9562b95c6e8a66b4cd081f09cc600bf7a364c46

Modified Files
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src/test/regress/expected/stats_import.out | 12 ++++++++++++
src/test/regress/sql/stats_import.sql      |  7 +++++++
2 files changed, 19 insertions(+)