pgsql: basebackup_to_shell: Add missing MarkGUCPrefixReserved()

basebackup_to_shell: Add missing MarkGUCPrefixReserved()

Oversight in c6306db24, as per a requirement from 88103567. All the
other modules in the tree, be they in contrib/ or src/test/modules/,
already do that.

Author: Bharath Rupireddy
Discussion: /messages/by-id/CALj2ACUy7q_KwSMda+2SHPSWep32tNUM8cXGRS3=-Vfodo9OUg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/7307988abdff6c948d87e6d9dc9aaaa1f4c5283f

Modified Files
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contrib/basebackup_to_shell/basebackup_to_shell.c | 2 ++
1 file changed, 2 insertions(+)