don't swallow exceptions when instanciating Scalafix

src/main/scala/scalafix/internal/sbt/BlockingCache.scala

@@ -9,23 +9,29 @@ class BlockingCache[K, V] {
 
  private val underlying = new ju.concurrent.ConcurrentHashMap[K, V]
 
+ private object SkipUpdate extends Exception
+
  // Evaluations of `transform` are guaranteed to be sequential for the same key
  def compute(key: K, transform: Option[V] => Option[V]): V = {
  // ju.Map.compute does not return the value if the BiFunction does not update it,
  // so we store it in a var to return it
- var unchangedValue: V = null.asInstanceOf[V]
+ var originalValue: V = null.asInstanceOf[V]
  Try(
  underlying.compute(
  key,
  new ju.function.BiFunction[K, V, V] {
  override def apply(key: K, prev: V): V = {
- unchangedValue = prev
- transform(Option(prev))
- // throw an exception if None is returned to skip reassignement
- .get
+ originalValue = prev
+ transform(Option(prev)).getOrElse(throw SkipUpdate)
  }
  }
  )
- ).getOrElse(unchangedValue)
+ ).fold(
+ {
+ case SkipUpdate => originalValue
+ case ex => throw ex
+ },
+ identity
+ )
  }
 }