Update sbt to 1.5.7

[scala-steward]

Updates org.scala-sbt:sbt from 1.5.5 to 1.5.7.
GitHub Release Notes - Version Diff

I'll automatically update this PR to resolve conflicts as long as you don't change it yourself.

If you'd like to skip this version, you can just close this PR. If you have any feedback, just mention me in the comments below.

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Have a fantastic day writing Scala!

Ignore future updates

Add this to your .scala-steward.conf file to ignore future updates of this dependency:

updates.ignore = [ { groupId = "org.scala-sbt", artifactId = "sbt" } ]

labels: library-update, early-semver-patch, semver-spec-patch, commit-count:1

[coveralls]

Pull Request Test Coverage Report for Build 1581915575

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 6 unchanged lines in 4 files lost coverage.
• Overall coverage remained the same at 67.683%

---

Files with Coverage Reduction	New Missed Lines	%
sequentially/src/main/scala/com/evolutiongaming/concurrent/sequentially/AsyncHandlerMap.scala	1	87.5%
sequentially/src/main/scala/com/evolutiongaming/concurrent/sequentially/AsyncMap.scala	1	83.33%
sequentially/src/main/scala/com/evolutiongaming/concurrent/sequentially/SequentialMap.scala	1	95.45%
sequentially/src/main/scala/com/evolutiongaming/concurrent/sequentially/SequentiallyAsync.scala	3	72.22%

Totals
Change from base Build 1440982230:	0.0%
Covered Lines:	111
Relevant Lines:	164

---

💛 - Coveralls

[scala-steward]

Superseded by #91.