Add tests for Bug#24264

Add tests for Bug#24264

* test/lisp/emacs-lisp/cl-seq-tests.el (cl-seq-test-bug24264):
Add test for Bug#24264.
(cl-seq-fill-test, cl-seq-replace-test)
(cl-seq-remove-test ,cl-seq-delete-test)
(cl-seq-remove-duplicates-test, cl-seq-substitute-test)
(cl-seq-nsubstitute-test, cl-seq-position-test)
(cl-seq-count-test, cl-seq-mismatch-test)
(cl-seq-search-test, cl-seq-test-bug24264):
Add tests for all functions in the file; test all keywords.