odsign_e2e_tests: do not assume time monotonicity across reboots

(cherry picked from commit a0dd228837fbbacb3d29445bdf027649567f94fb)

Fix: 194365586
Test: atest --iterations 10 com.android.tests.odsign.OnDeviceSigningHostTest
Merged-In: I824da7fb9bfc0c455c852f99d2564e89728170ea
Change-Id: I294f96474ac5c9265900f762020f6e65b934a046
1 file changed