Prefer File.getCanonicalFile over Path.normalize

The former normalizes Windows 8.3 paths to long paths, whereas the
latter doesn't.

os/src/Path.scala

@@ -384,7 +384,14 @@ object Path {
       throw PathError.AbsolutePathOutsideRoot
     }
 
-    val normalized = f.normalize()
+    fromNIO(f)
+  }
+
+  private def fromNIO(p: java.nio.file.Path): Path = {
+    // On Windows, File.getCanonicalFile normalizes 8.3 paths as long paths,
+    // whereas Path.normalize doesn't. So we use the former here.
+    require(p.isAbsolute, s"$p is not an absolute path")
+    val normalized = p.toFile.getCanonicalFile.toPath
     new Path(normalized)
   }
 
@@ -437,8 +444,8 @@ class Path private[os](val wrapped: java.nio.file.Path)
 
   def /(chunk: PathChunk): ThisType = {
     if (chunk.ups > wrapped.getNameCount) throw PathError.AbsolutePathOutsideRoot
-    val resolved = wrapped.resolve(chunk.toString).normalize()
-    new Path(resolved)
+    val resolved = wrapped.resolve(chunk.toString)
+    Path.fromNIO(resolved)
   }
   override def toString = wrapped.toString