test khronos translator as backend

[simeonschaub]

Requires JuliaPackaging/Yggdrasil#14212 and
JuliaGPU/GPUCompiler.jl#879 to pass.

Deletes one float atomics test I added before we had proper support for
float atomics and which is not really relevant anymore. (ref
KhronosGroup/SPIRV-LLVM-Translator#3404)

[codecov]

Codecov Report

❌ Patch coverage is 45.45455% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.32%. Comparing base (3f0d3f0) to head (fa41b62).

Files with missing lines	Patch %	Lines
src/compiler/compilation.jl	45.45%	6 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #458      +/-   ##
==========================================
- Coverage   80.74%   80.32%   -0.43%     
==========================================
  Files          13       13              
  Lines         909      920      +11     
==========================================
+ Hits          734      739       +5     
- Misses        175      181       +6     

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[simeonschaub]

Deletes one float atomics test I added before we had proper support for
float atomics and which is not really relevant anymore.

Just realized I was thinking of #453, which isn't merged yet, so we might want to merge that PR first