pgsql: Fixes for comments in test_bitmapset

Fixes for comments in test_bitmapset

This fixes a typo in the sql/expected test files and removes a
leftover comment from test_bitmapset.c from when the functions
invoked bms_free.

Author: Daniel Gustafsson <daniel@yesql.se>
Reported-by: David Rowley <dgrowleyml@gmail.com>
Discussion: https://postgr.es/m/978D21E8-9D3B-40EA-A4B1-F87BABE7868C@yesql.se

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/a1b064e4b22686ecaecdf1cee0abfe53b81f6aaf

Modified Files
--------------
src/test/modules/test_bitmapset/expected/test_bitmapset.out | 2 +-
src/test/modules/test_bitmapset/sql/test_bitmapset.sql      | 2 +-
src/test/modules/test_bitmapset/test_bitmapset.c            | 2 --
3 files changed, 2 insertions(+), 4 deletions(-)