Fix dumb-jump-goto-file-line-test for Emacs 29 (jacktasia#442)

In Emacs 29, the ring-insert function is not called anymore when
dumb-jump-goto-file-line is called. The corresponding test relied on an
implementation detail of xref-push-marker-stack. See the longer
explanation in jacktasia#442.

Fix the test by guarding the check for the ring-insert call with a
Emacs version check.

Author: Joerg Bornemann

test/dumb-jump-test.el

@@ -348,7 +348,8 @@
 (ert-deftest dumb-jump-goto-file-line-test ()
   (let ((js-file (f-join test-data-dir-proj1 "src" "js" "fake.js")))
     (with-mock
-     (mock (ring-insert * *))
+     (when (version< emacs-version "29")
+       (mock (ring-insert * *)))
      (dumb-jump-goto-file-line js-file 3 0)
      (should (string= (buffer-file-name) js-file))
      (should (= (line-number-at-pos) 3)))))