Use Resource for temporarily creating and removing files

[fthomas]

Using Resource makes it easier to compose those functions compared to
nesting F[A] => F[A].

[codecov]

Codecov Report

Merging #2351 (1de2281) into master (c0a00ab) will decrease coverage by 0.09%.
The diff coverage is 88.23%.

@@            Coverage Diff             @@
##           master    #2351      +/-   ##
==========================================
- Coverage   80.25%   80.16%   -0.10%     
==========================================
  Files         138      138              
  Lines        2391     2374      -17     
  Branches       60       55       -5     
==========================================
- Hits         1919     1903      -16     
+ Misses        472      471       -1     

Impacted Files	Coverage Δ
...g/scalasteward/core/buildtool/maven/MavenAlg.scala	87.50% <66.66%> (ø)
...a/org/scalasteward/core/buildtool/sbt/SbtAlg.scala	97.29% <88.88%> (+1.29%)	⬆️
...org/scalasteward/core/application/StewardAlg.scala	40.00% <100.00%> (ø)
...org/scalasteward/core/buildtool/mill/MillAlg.scala	86.95% <100.00%> (ø)
.../main/scala/org/scalasteward/core/io/FileAlg.scala	96.66% <100.00%> (-0.40%)	⬇️

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