Fix typo: MacOS 26 -> MacOS 16

[asuessenbach]

No description provided.

[M2-TE]

@asuessenbach MacOS 26 was actually correct (I had to double check a few times in the past too):

Vulkan-Hpp/.github/workflows/build.yml

Lines 18 to 20 in 1520807

	{ os: macos-14, cxx: /usr/bin/clang++, c: /usr/bin/clang, arch: x64, gen: Ninja, cxx_max: 23 },
	{ os: macos-15, cxx: /usr/bin/clang++, c: /usr/bin/clang, arch: x64, gen: Ninja, cxx_max: 23 },
	{ os: macos-26, cxx: /usr/bin/clang++, c: /usr/bin/clang, arch: x64, gen: Ninja, cxx_max: 23 },

Here's the MacOS image selection: https://github.com/actions/runner-images/tree/main/images/macos

[asuessenbach]

Ahm... that's... unexpected.

Ok, I'll try to revert this. Thanks for that hint!