pgsql: Clean up role created in new subscription test.

Clean up role created in new subscription test.

This oversight broke repeated runs of "make installcheck".

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e9d202a1499d6a70e80d080fcdba07fe6707845d

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