pgsql: Repair find_inheritance_children with no active snapshot

Repair find_inheritance_children with no active snapshot

When working on a scan with only a catalog snapshot, we may not have an
ActiveSnapshot set.  If we were to come across a detached partition,
that would cause a crash.  Fix by only ignoring detached partitions when
there's an active snapshot.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4131f755d548f74eba56285dc674f1f26e4ed6b4

Modified Files
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src/backend/catalog/pg_inherits.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)