pgsql: Fix assorted resource leaks in new pg_createsubscriber code.

Fix assorted resource leaks in new pg_createsubscriber code.

Various error paths did not release resources before returning.
While it's likely that the program would just exit shortly later,
none of the functions in question have summary exit(1) calls,
so they should not be assuming that.

Ranier Vilela and Tom Lane, per reports from Coverity

Discussion: https://postgr.es/m/CAEudQAr2_SZFxB4kXJiL4+2UaNZxUk5UBJtj0oXyJYMGZu-03g@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/91cbb4b492cbea889e8392a85e246c1778ca2a45

Modified Files
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src/bin/pg_basebackup/pg_createsubscriber.c | 17 +++++++++++++----
1 file changed, 13 insertions(+), 4 deletions(-)