Silence some warnings in tests

* test/lisp/emacs-lisp/package-tests.el
(package-test-suffix-matches): Evaluate lambda.
(package-test-list-filter-marked):
* test/lisp/vc/vc-tests.el
(vc-test--run-maybe-unsupported-function):
* test/src/undo-tests.el (undo-test-skip-invalidated-markers):
Silence "unused local variable" warnings.
* test/lisp/imenu-tests.el (imenu-simple-scan-deftest): Fix
docstring.  Don't shadow global major-mode.

1 files changed, 1 insertions, 1 deletions

diff --git a/test/src/undo-tests.el b/test/src/undo-tests.el
index 13335a9bb10..b26a276c61b 100644
--- a/test/src/undo-tests.el
+++ b/test/src/undo-tests.el
@@ -452,7 +452,7 @@ Demonstrates bug 25599."
     (insert ";; aaaaaaaaa
 ;; bbbbbbbb")
     (let ((overlay-modified
-           (lambda (ov after-p _beg _end &optional length)
+           (lambda (ov after-p _beg _end &optional _length)
              (unless after-p
                (when (overlay-buffer ov)
                  (delete-overlay ov))))))