Two test failures on v16 (compared to v14)

Just an FYI. Running the same test suite against V16 triggered two failures.

First, a test of getting the direct members of a role failed.
Returned one more role. The role that created the introspected role.
That's the new CREATEROLE semantic, which adds the role creator
as a direct member of the created role, with admin option.

Second, a LO test failed to open a given OID.
The test starts a read-only transaction, then tries a loOpen(oid,
INV_WRITE),
but does only a loRead(). Now in v16, the loOpen fails, returning -1, while
it used to be OK.
So this must be a bug fix of some kind I guess. Using INV_READ fixed the
test.

I was not expecting failures, but both have good reasons and are easily
fixed. FWIW. --DD