pgsql: Fix unsafe extraction of the OID part of a relation filename.

Fix unsafe extraction of the OID part of a relation filename.

Commit 8694cc96b did this randomly differently from other callers of
parse_filename_for_nontemp_relation(). Perhaps unsurprisingly,
the randomly different way is wrong; it fails to ensure the
extracted string is null-terminated. Per buildfarm member skink.

Discussion: /messages/by-id/14453.1522001792@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d0c0c894533f906b13b79813f02b2982ac675074

Modified Files
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src/backend/replication/basebackup.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)