Upstream anyeltypedual for FixedSizeDiffCache

[jClugstor]

Checklist

• Appropriate tests were added
• Any code changes were done in a way that does not break public API
• All documentation related to code changes were updated
• The new code follows the
  contributor guidelines, in particular the SciML Style Guide and
  COLPRAC.
• Any new documentation only uses public API

Additional context

Upstreaming https://github.com/SciML/PreallocationTools.jl/blob/master/test/gpu_all.jl#L4-L5