pgsql: Add tests of the CREATEROLE attribute

Add tests of the CREATEROLE attribute

The current regression tests do not contain much testing of CREATEROLE.
This patch, extracted from a larger patch set to modify how that
feature works, remedies that omission.

Author: Mark Dilger

Discussion: /messages/by-id/D9065DFB-56DB-4E89-A73E-DB8CC2C746C6@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e9d4001ec592bcc9a3332547cb1b0211e8794f38

Modified Files
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src/test/regress/expected/create_role.out | 145 ++++++++++++++++++++++++++++++
src/test/regress/parallel_schedule | 2 +-
src/test/regress/sql/create_role.sql | 138 ++++++++++++++++++++++++++++
3 files changed, 284 insertions(+), 1 deletion(-)