Revert "sbt.ExtractDependencies: avoid false dependencies"

This reverts commit 57641b9.

Using `Type#select` instead of `Type#member` turned out to not help at
all in avoiding false dependencies, you can still get a symbol whose
denotation does not reallyExists. A proper fix for this issue is
contained in the next commit.

Author: smarter

compiler/src/dotty/tools/dotc/sbt/ExtractDependencies.scala

@@ -175,7 +175,7 @@ private class ExtractDependenciesCollector(implicit val ctx: Context) extends tp
   override def traverse(tree: Tree)(implicit ctx: Context): Unit = {
     tree match {
       case Import(expr, selectors) =>
-        def lookupImported(name: Name) = expr.tpe.select(name).typeSymbol
+        def lookupImported(name: Name) = expr.tpe.member(name).symbol
         def addImported(name: Name) = {
           // importing a name means importing both a term and a type (if they exist)
           addDependency(lookupImported(name.toTermName))