The test may be run on S builds older than itself, in which case the
resource ID may not match. Query the resource ID dynamically instead of
using the constant.
IpSecAlgorithm is not updatable in S, which is why it can use
hidden/unstable platform resources, so the test could also be skipped
altogether on S. But considering that keeping it around is not very
costly yet, this change fixes it for running on S.
Bug: 197489543
Test: atest IpSecAlgorithmTest
Change-Id: I533eede3a360a8db9089e65e017b9d7453b35539
ae7508f9b5