Add new replaceAllInSliding strategy

[fthomas]

No description provided.

[codecov]

Codecov Report

Merging #527 into master will increase coverage by 0.11%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master     #527      +/-   ##
==========================================
+ Coverage   55.08%   55.19%   +0.11%     
==========================================
  Files          64       64              
  Lines         797      799       +2     
  Branches       34       37       +3     
==========================================
+ Hits          439      441       +2     
  Misses        358      358

Impacted Files	Coverage Δ
...ain/scala/org/scalasteward/core/model/Update.scala	100% <100%> (ø)	⬆️
.../scala/org/scalasteward/core/nurture/EditAlg.scala	100% <100%> (ø)	⬆️

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[fthomas]

The motivation for this new heuristic is this test: https://github.com/fthomas/scala-steward/pull/527/files#diff-4afd9d1aeae9d83e852850cdf8b9b256