pgsql: Update comments to match location of definition

Update comments to match location of definition

Commit cc50080a82 rearranged testsuites to reduce dependencies, but
missed to update a comment when moving an operator class definition.
Also fix a typo in that same comment while here.

Author: Suraj Kharage <suraj.kharage@enterprisedb.com>
Discussion: /messages/by-id/CAF1DzPWXd2yq9_=P905cEypMVKw3ho+Fpj4HwJ4ta8T-eh+Yig@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/aca17fe206a9b8b73ec76f10a3256f1bf019e1a6

Modified Files
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src/test/regress/expected/alter_table.out | 2 +-
src/test/regress/expected/hash_part.out | 2 +-
src/test/regress/expected/partition_prune.out | 2 +-
src/test/regress/sql/alter_table.sql | 2 +-
src/test/regress/sql/hash_part.sql | 2 +-
src/test/regress/sql/partition_prune.sql | 2 +-
6 files changed, 6 insertions(+), 6 deletions(-)