pgsql: Schema-qualify references in test_ddl_deparse test script.

Schema-qualify references in test_ddl_deparse test script.

This omission seems to be what is causing buildfarm failures on crake.

Security: CVE-2018-1058

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3300e876cd45cf169d981fa53f9c9e8289ee3c82

Modified Files
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src/test/modules/test_ddl_deparse/expected/test_ddl_deparse.out | 6 +++---
src/test/modules/test_ddl_deparse/sql/test_ddl_deparse.sql      | 6 +++---
2 files changed, 6 insertions(+), 6 deletions(-)