pgsql: Add test case for ON DELETE NO ACTION/RESTRICT

Add test case for ON DELETE NO ACTION/RESTRICT

This was previously not covered at all; function
RI_FKey_restrict_del() was not exercised in the tests.

Reviewed-by: Alvaro Herrera <alvherre@2ndquadrant.com>
Reviewed-by: Mi Tar <mmitar@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/7ae17c95-0c99-d420-032a-c271f510112b@2ndquadrant.com/

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/74bd06648b720bb48f50bd32848f2f3cf2deb1f6

Modified Files
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src/test/regress/expected/foreign_key.out | 10 ++++++++--
src/test/regress/sql/foreign_key.sql      |  6 ++++--
2 files changed, 12 insertions(+), 4 deletions(-)