tests: lib: custom_lib: require CMake 3.20

Zephyr now requires CMake >= 3.20.

Signed-off-by: Gerard Marull-Paretas <gerard.marull@nordicsemi.no>

Author: gmarull

tests/lib/custom_lib/CMakeLists.txt

@@ -1,7 +1,7 @@
 # Copyright (c) 2021, Legrand North America, LLC.
 # SPDX-License-Identifier: Apache-2.0
 
-cmake_minimum_required(VERSION 3.13.1)
+cmake_minimum_required(VERSION 3.20.0)
 find_package(Zephyr REQUIRED HINTS $ENV{ZEPHYR_BASE})
 project(custom_lib)