[DO NOT MERGE][Harness Separation] Update cts.mk to point to the new harness repo

CTS harness code is moved to the new git project.
Update cts.mk to point to the new repo.

Bug: 78461075
Bug: 79201478
Bug: 79695450
Test: make cts -j32 WITH_DEXPREOPT_BOOT_IMG_AND_SYSTEM_SERVER_ONLY=true
TARGET_PRODUCT=aosp_arm64
Test: cts-tradefed run cts --compatibility:include-filter
CtsGestureTestCases
Test: cts/run_unit_tests.sh
Test: make gts -j32 WITH_DEXPREOPT_BOOT_IMG_AND_SYSTEM_SERVER_ONLY=true
TARGET_PRODUCT=aosp_arm64

Change-Id: I94c03071ec3db5a52c0fc0185bf69e2e57da9b21