pgsql: Add regression test for ALTER TABLE .. NO INHERIT on typed table

Add regression test for ALTER TABLE .. NO INHERIT on typed tables

This test addition has come up as a suggestion by me, while discussing a
patch that manipulates the area of the code related to this command
pattern.

Author: Chao Li <li.evan.chao@gmail.com>
Discussion: /messages/by-id/CAEoWx2kggo1N2kDH6OSfXHL_5gKg3DqQ0PdNuL4LH4XSTKJ3-g@mail.gmail.com

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/cbf9a72993ec8148cdf1925e414e0b4e27f20f2f

Modified Files
--------------
src/test/regress/expected/typed_table.out | 4 +++-
src/test/regress/sql/typed_table.sql | 3 ++-
2 files changed, 5 insertions(+), 2 deletions(-)