A GitHub Action to add Scala utilities to the PATH.

• sbt++field - Start sbt with the Scala version described by an sbt build field.

  > grep -h 'val scala.*=' project/*.scala
      val scala2          = "2.13.6"
      val scala3          = "3.0.2"
  
  > sbt++field scala2 test
  # Runs sbt ++2.13.6 test

• sbt-const - Extract the string literal from a val or def field in your sbt build.

  Example:

  > grep -h 'val scala.*=' project/*.scala
      val scala2          = "2.13.6"
      val scala3          = "3.0.2"
  
  > sbt-const scala2
  2.13.6