pgsql: Add regression test for system catalog toast tables

Add regression test for system catalog toast tables

For the moment, this just records which system catalogs have toast
tables right now. Future patches will possibly change that set.

from Tom Lane via Joe Conway

Discussion: /messages/by-id/84ddff04-f122-784b-b6c5-3536804495f8@joeconway.com/

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ecd6b4342ad9f867e62979e85efa8fdb5fc904e5

Modified Files
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src/test/regress/expected/misc_sanity.out | 67 +++++++++++++++++++++++++++++++
src/test/regress/sql/misc_sanity.sql | 15 +++++++
2 files changed, 82 insertions(+)