Pass update branch to createBranch and listingBranch

[fthomas]

These functions do not need to compute the update branch because it
has already been done in NurtureAlg before they are called.

[codecov]

Codecov Report

Merging #2294 (39ce572) into master (90cf411) will not change coverage.
The diff coverage is 50.00%.

@@           Coverage Diff           @@
##           master    #2294   +/-   ##
=======================================
  Coverage   77.83%   77.83%           
=======================================
  Files         135      135           
  Lines        2287     2287           
  Branches       51       51           
=======================================
  Hits         1780     1780           
  Misses        507      507           

Impacted Files	Coverage Δ
...ala/org/scalasteward/core/nurture/NurtureAlg.scala	0.00% <0.00%> (ø)
...main/scala/org/scalasteward/core/vcs/package.scala	100.00% <100.00%> (ø)

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