CompatHelper: bump compat for Setfield to 0.8, (keep existing compat)

[github-actions]

This pull request changes the compat entry for the Setfield package from 0.3, 0.4, 0.5, 0.6, 0.7 to 0.3, 0.4, 0.5, 0.6, 0.7, 0.8.
This keeps the compat entries for earlier versions.

Note: I have not tested your package with this new compat entry.
It is your responsibility to make sure that your package tests pass before you merge this pull request.

[codecov]

Codecov Report

Merging #179 (caba984) into master (dd3d4e3) will decrease coverage by 1.34%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #179      +/-   ##
==========================================
- Coverage   80.53%   79.18%   -1.35%     
==========================================
  Files           9        9              
  Lines         452      490      +38     
==========================================
+ Hits          364      388      +24     
- Misses         88      102      +14     

Impacted Files	Coverage Δ
src/countingsort.jl	12.32% <0.00%> (-1.96%)	⬇️
src/utils.jl	72.30% <0.00%> (-0.91%)	⬇️
src/reduce.jl	98.61% <0.00%> (+0.03%)	⬆️
src/foreach.jl	82.92% <0.00%> (+0.06%)	⬆️
src/quicksort.jl	98.01% <0.00%> (+0.10%)	⬆️
src/mergesort.jl	95.78% <0.00%> (+0.13%)	⬆️
src/map.jl	96.42% <0.00%> (+0.27%)	⬆️
src/basesizes.jl	76.92% <0.00%> (+1.92%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update dd3d4e3...caba984. Read the comment docs.