Improve asserts in MetadataRepositoryManagerTest

Change-Id: Ia6c005550909c1119f9e93bc4a3f915e4a4a56ab
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>
Reviewed-on: https://git.eclipse.org/r/c/equinox/rt.equinox.p2/+/188532
1 file changed