Adding an admin check before calling downloadSubscriptionPrivileged.

When a device administrator requests a download without carrier privileges the download should be allowed since this is encountered in the resolvable error flow path.

Bug: 401243419
Test: Verified with test dpc that the download is working as expected in DO as well as COPE on Pixel 7 by adding 2 active eSIMs and then trying to add a third active eSIM which results in a resolvable error.
Flag: EXEMPT BugFix
Change-Id: I8bcb7a348f35ed4e84cedf16237c2ccf1f5c9149