fix path adjustment of inline test files in snow-chibi package command

lib/chibi/snow/commands.scm

@@ -592,10 +592,13 @@
                     data-files))
                (tar-files
                 (reverse
-                 (append (if test
+                 (append
+                  (cond
+                   ((pair? test) (list test))
+                   (test
                     `((rename ,test
-                                       ,(path-strip-leading-parents test)))
-                             '())
+                              ,(path-strip-leading-parents test))))
+                   (else '()))
                   docs tar-data-files files))))
           (cons `(package
                   ,@(reverse res)