pgsql: Fix one more portability shortcoming in new test_pg_dump test.

Fix one more portability shortcoming in new test_pg_dump test.

If the bootstrap superuser's name requires quoting, regroleout
will supply double quotes ... but the result of CURRENT_USER
is just the literal name.  Apply quote_ident() to ensure a match.

Per Andrew Dunstan's off-list investigation of buildfarm member
prion's failures.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d12b4ba1bd3eedd862064cf1dad5ff107c5cba90

Modified Files
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src/test/modules/test_pg_dump/expected/test_pg_dump.out | 8 ++++----
src/test/modules/test_pg_dump/sql/test_pg_dump.sql      | 8 ++++----
2 files changed, 8 insertions(+), 8 deletions(-)