ci: Test cmake_minimum_required

[juan-lunarg]

trafficstars

Ensures project configures with 3.13 since it's very easy to write code that doesn't respect the minimum.

[dinord]

As maintainers, we do not use GitHub actions CI. Instead, we have a proprietary workflow that runs the scripts in https://github.com/google/googletest/tree/main/ci. Our existing GHA are purely maintained by the open-source community.

Despite that, sometimes users believe GoogleTest is broken because GHA is broken, even though our internal workflows are green. Can we make the CMake CI as similar as possible to the internally used script? https://github.com/google/googletest/blob/ec4fed93217bc2830959bb8e86798c1d86956949/ci/linux-presubmit.sh#L45

[juan-lunarg]

Closing this PR since I wasn't aware of the internal CI beforehand and am not sure how much contributing this would add to the project.