Add artifact migration for sbt-proguard

[eed3si9n]

See sbt/sbt-proguard#47

[codecov]

Codecov Report

Merging #2397 (6901f0f) into master (fa4385e) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2397   +/-   ##
=======================================
  Coverage   80.43%   80.43%           
=======================================
  Files         140      140           
  Lines        2392     2392           
  Branches       43       43           
=======================================
  Hits         1924     1924           
  Misses        468      468           

---

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 fa4385e...6901f0f. Read the comment docs.