Windows debug builds modify global CRT error modes

Hi,

On Windows, using a debug build of `vulkan-1.dll` changes global CRT error reporting modes.
Here's the code in question: https://github.com/KhronosGroup/Vulkan-Loader/blob/1a337fe32d4d5be2ec2af7e02647005aeb358faa/loader/loader_windows.c#L91-L95

While this is probably useful for Vulkan-Loader's own tests in CI, it's not expected behavior for users who might want to set their own error report modes.
I would suggest moving the error mode code to the test runner instead.

Start in loader/loader_windows.c at the linked lines 91-95 and inspect where the debug CRT error modes are set. Then locate the test runner that needs this behavior and verify that tests still pass while using vulkan-1.dll no longer changes users' global CRT error modes.

Written by the indexing model from the issue text.