pgsql: Fix small memory leak in get_dbname_oid_list_from_mfile().

Fix small memory leak in get_dbname_oid_list_from_mfile().

Coverity complained that this function leaked the dumpdirpath string,
which it did. But we don't need to make a copy at all, because
there's not really any point in trimming trailing slashes from the
directory name here. If that were needed, the initial
file_exists_in_directory() test would have failed, since it doesn't
bother with that (and neither does anyplace else in this file).
Moreover, if we did want that, reimplementing canonicalize_path()
poorly is not the way to proceed. Arguably, all of this code should
be reexamined with an eye to using src/port/path.c's facilities, but
for today I'll settle for getting rid of the memory leak.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/bb53b8d359d33f10b6274be743c42f6e8ecfbb84

Modified Files
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src/bin/pg_dump/pg_restore.c | 16 +++-------------
1 file changed, 3 insertions(+), 13 deletions(-)