cmake: Bump minimum required version to 3.10
We are using GoogleTest module introduced in 3.9.
None of Debian / Ubuntu distributions versions provides CMake 3.9. The 3.10 is selected because this is the version provided in Ubuntu 18.04 LTS.
# Copyright 2016-2019 The EVMC Authors.
# Licensed under the Apache License, Version 2.0.
-cmake_minimum_required(VERSION 3.5)
+cmake_minimum_required(VERSION 3.10)
if(POLICY CMP0074)
cmake_policy(SET CMP0074 NEW)
