Use `advice-flet' in place of `cl-letf' to avoid primitive redefinition

Use `advice-flet' in place of `cl-letf' to avoid primitive redefinition

	* test/lisp/time-stamp-tests.el (with-time-stamp-system-name): Use
	`advice-flet' to advice primitive avoiding redefinition.

	* test/lisp/tempo-tests.el (tempo-p-element-test)
	(tempo-P-element-test, tempo-r-element-test)
	(tempo-s-element-test, tempo-r>-element-test): Likewise.

	* test/lisp/subr-tests.el (subr-tests-bug22027): Likewise.

	* test/lisp/shadowfile-tests.el (shadow-test00-clusters)
	(shadow-test01-sites, shadow-test06-literal-groups)
	(shadow-test07-regexp-groups): Likewise.

	* test/lisp/replace-tests.el (replace-tests-with-undo): Likewise.

	* test/lisp/play/dissociate-tests.el
	(dissociate-tests-dissociated-press): Likewise.

	* test/lisp/net/tramp-tests.el (tramp-test10-write-region)
	(tramp-test21-file-links): Likewise.

	* test/lisp/kmacro-tests.el (kmacro-tests-call-macro-hint-and-repeat)
	(kmacro-tests-repeat-on-last-key)
	(kmacro-tests-repeat-view-and-run)
	(kmacro-tests-bind-to-key-with-key-sequence-in-use): Likewise.

	* test/lisp/files-tests.el (files-tests-read-file-in-~): Likewise.

	* test/lisp/emacs-lisp/rmc-tests.el (test-read-multiple-choice):
	Likewise.

	* test/lisp/bookmark-tests.el (bookmark-test-bmenu-locate):
	Likewise.

	* test/lisp/abbrev-tests.el
	(inverse-add-abbrev-skips-trailing-nonword)
	(inverse-add-abbrev-skips-trailing-nonword/positive-arg)
	(inverse-add-abbrev-skips-trailing-nonword/negative-arg): Likewise.