bounding UnsafeAtomics and UnsafeAtomicsLLVM

[leios]

This should fix #305 so users to not need to manually add UnsafeAtomics separately for CPU atomics and also JuliaRegistries/General#62061 (comment)

[codecov]

Codecov Report

Merging #311 (2a19865) into master (c0d0551) will increase coverage by 0.67%.
The diff coverage is n/a.

❗ Current head 2a19865 differs from pull request most recent head 0b7c850. Consider uploading reports for the commit 0b7c850 to get more accurate results

@@            Coverage Diff             @@
##           master     #311      +/-   ##
==========================================
+ Coverage   76.46%   77.13%   +0.67%     
==========================================
  Files          13       13              
  Lines         888      888              
==========================================
+ Hits          679      685       +6     
+ Misses        209      203       -6     

Impacted Files	Coverage Δ
lib/CUDAKernels/src/CUDAKernels.jl	69.04% <0.00%> (+3.57%)	⬆️

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