Do not embed build path

https://issues.guix.gnu.org/44835

diff --git a/gnu/ci.scm b/gnu/ci.scm
index 5548d9560e..0bacfbe025 100644
--- a/gnu/ci.scm
+++ b/gnu/ci.scm
@@ -488,7 +488,8 @@ valid."
 Return #f if no such checkout is found."
   (let ((current-root
          (canonicalize-path
-          (string-append (dirname (current-filename)) "/.."))))
+          (string-append (dirname (search-path %load-path "gnu/ci.scm"))
+                         "/.."))))
     (find (lambda (argument)
             (and=> (assq-ref argument 'file-name)
                    (lambda (name)
