pgsql: Improve test coverage for changes to inplace-updated catalogs.

Improve test coverage for changes to inplace-updated catalogs.

This covers both regular and inplace changes, since bugs arise at their
intersection. Where marked, these witness extant bugs. Back-patch to
v12 (all supported versions).

Reviewed (in an earlier version) by Robert Haas.

Discussion: https://postgr.es/m/[email protected]

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/dd8008e8ec956845a3a25060e596994192489f0a

Modified Files
--------------
src/bin/pgbench/t/001_pgbench_with_server.pl | 28 +++
src/test/isolation/expected/eval-plan-qual.out | 26 +++
src/test/isolation/expected/inplace-inval.out | 32 +++
.../isolation/expected/intra-grant-inplace-db.out | 28 +++
.../isolation/expected/intra-grant-inplace.out | 225 +++++++++++++++++++++
src/test/isolation/isolation_schedule | 3 +
src/test/isolation/specs/eval-plan-qual.spec | 21 ++
src/test/isolation/specs/inplace-inval.spec | 38 ++++
.../isolation/specs/intra-grant-inplace-db.spec | 46 +++++
src/test/isolation/specs/intra-grant-inplace.spec | 153 ++++++++++++++
src/test/recovery/t/027_stream_regress.pl | 34 ++++
src/test/regress/expected/database.out | 15 ++
src/test/regress/expected/merge.out | 11 +
src/test/regress/parallel_schedule | 2 +-
src/test/regress/sql/database.sql | 17 ++
src/test/regress/sql/merge.sql | 14 ++
16 files changed, 692 insertions(+), 1 deletion(-)