pgsql: Make test_decoding ddl.out shorter

Make test_decoding ddl.out shorter

Some of the test_decoding test output was extremely wide, because it
deals with massive toasted values, and the aligned mode causes psql to
produce 200kB of whitespace and dashes. Change to unaligned mode
temporarily to avoid that behavior.

Backpatch to 14, where it applies cleanly.

Discussion: https://postgr.es/m/20230405103953.sxleixp3uz5lazst@alvherre.pgsql

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3bb8b9342f8abe81af47ff7e5217865107cc15b3

Modified Files
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contrib/test_decoding/expected/ddl.out | 316 ++++++++++++++++-----------------
contrib/test_decoding/sql/ddl.sql      |   6 +
2 files changed, 164 insertions(+), 158 deletions(-)