Merge topic 'findvulkan-improvements'

7974fcd1a7 FindVulkan: remove noop on CMAKE_MODULE_PATH in tests
acdb5fe0e8 FindVulkan: Add component for `glslc` and `glslangValidator`
998ee49779 FindVulkan: ensure policy CMP0057 is NEW to use `IN_LIST` with `if()`
9f8720e74c FindVulkan: Add component for `glslang`
8d133f49e3 FindVulkan: Add component for `SPIRV-Tools`
6e4d20921d FindVulkan: Add component for `shaderc_combined`
2f46b8d723 FindVulkan: Move `mark_as_advanced` right after `find_*` calls.
08a420af4a FindVulkan: Factorize code for library/executable search

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !7225