pgsql: Fix comment in regression tests for large objects

Fix comment in regression tests for large objects

The values assigned to INV_WRITE and INV_READ were reversed in the
tests, which would be confusing when writing tests specific to read or
write operations on LOs.

Author: Yugo Nagata
Discussion: https://postgr.es/m/20220527153028.61a4608f66abcd026fd3806f@sraoss.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/664da2a389e5d1d4ebf0f98c82997739cd496e8e

Modified Files
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src/test/regress/expected/largeobject.out   | 4 ++--
src/test/regress/expected/largeobject_1.out | 4 ++--
src/test/regress/sql/largeobject.sql        | 4 ++--
3 files changed, 6 insertions(+), 6 deletions(-)