pgsql: Display 'password_required' option for \dRs+ command.

Display 'password_required' option for \dRs+ command.

The commit c3afe8cf5a added a new subscription option 'password_required'
which should be shown with \dRs+ command.

Author: Vignesh C
Reviewed-by: Amit Kapila, Robert Haas
Discussion: https://postgr.es/m/CAA4eK1LRz5sCZxwCW6OtpjLtWPvRwBihQOM4jzQm6ppfpexqGA@mail.gmail.com
Discussion: https://postgr.es/m/9DFC88D3-1300-4DE8-ACBC-4CEF84399A53@enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/19e65dff38bdccdf2cac7f2083342101df6bea57

Modified Files
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src/bin/psql/describe.c                    |   4 +-
src/test/regress/expected/subscription.out | 151 +++++++++++++++--------------
src/test/regress/sql/subscription.sql      |   2 +
3 files changed, 84 insertions(+), 73 deletions(-)