fix(GODT-2963): Use multi error to report file removal errors

Do not abort removing files on first error. Collect errors and try to
remove as many as possible. This would cause some state files to not be
removed on windows.

pkg/files/removal.go

@@ -72,11 +72,12 @@ func remove(dir string, except ...string) error {
 
 	sort.Sort(sort.Reverse(sort.StringSlice(toRemove)))
 
+	var multiErr error
 	for _, target := range toRemove {
 		if err := os.RemoveAll(target); err != nil {
-			return err
+			multiErr = multierror.Append(multiErr, err)
 		}
 	}
 
-	return nil
+	return multiErr
 }