cmake: Fix CMP0026 policy deprecation warning

CMake 3.19+ started to issue warnings if this policy is set to OLD:

CMake Deprecation Warning at test/CMakeLists.txt:143 (cmake_policy):
  The OLD behavior for policy CMP0026 will be removed from a future version
  of CMake.

  The cmake-policies(7) manual explains that the OLD behaviors of all
  policies are deprecated and that a policy should be set to OLD only under
  specific short-term circumstances.  Projects should be ported to the NEW
  behavior and not rely on setting a policy to OLD.

0 files changed, 0 insertions, 0 deletions