pgsql: DROP ROLE regress_role_limited_admin at end of test

DROP ROLE regress_role_limited_admin at end of test

This is required by project policy, and I overlooked the need for
it (again) by accident.

Reported by Álvaro Herrara.

Discussion: http://postgr.es/m/20230126114659.x3yuypot7p6zj73c@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/14fb38626f3ff0f96144cd7535ce5feaba3a18a0

Modified Files
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src/test/regress/expected/create_role.out | 1 +
src/test/regress/sql/create_role.sql      | 1 +
2 files changed, 2 insertions(+)