Add gsk vulkan tests

Add a testsuite called gsk-compare-vulkan to run the gsk renderer tests with the Vulkan renderer.

The current stats:

Ok:                 184
Expected Fail:      0
Fail:               204
Unexpected Pass:    0
Skipped:            2
Timeout:            0

For now, we mark all the tests as failing to avoid ci breakage. To run the tests locally, you can do:

meson test -C_build --suite gsk-compare-vulkan