Remove shader variants from msaa sample

[tomadamatkinson]

Description

Contribution towards #1107

Removes shader variant usage from MSAA (other than base shaders)

Keeps existing behavior by creating two pipelines. One with MS Depth enabled and one without

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[tomadamatkinson]

This line is what replaces existing behavior

[tomadamatkinson]

This define is never set anywhere so i removed it

[asuessenbach]

For whatever reason, I can't get this PR to compile locally.
Something about a failing custom build on shaders\ray_tracing_position_fetch\hlsl\closesthit.rchit.hlsl?

Maybe you could rebase against main?

[asuessenbach]

For whatever reason, I don't get that build error anymore!

[asuessenbach]

Maybe add outline_ms_depth.frag under SHADER_FILES_GLSL in CMakeLists.txt.

[marty-johnson59]

3 approvals - merging