pgsql: Revert setting client_min_messages to 'debug1' in new tests.

Revert setting client_min_messages to 'debug1' in new tests.

The buildfarm doesn't like this, because some buildfarm members have
log_statement = 'all'.  We could change the log level of the messages
instead, but Tom doesn't like that.  So let's do this instead, at
least for now.

Patch by Sergei Kornilov, applied here in reverse.

Discussion: http://postgr.es/m/2123251552490241@myt6-fe24916a5562.qloud-c.yandex.net

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5655565c077c53b6e9b4b9bfcdf96439cf3af065

Modified Files
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src/test/regress/expected/alter_table.out | 19 -------------------
src/test/regress/sql/alter_table.sql      |  5 -----
2 files changed, 24 deletions(-)