Fix creation of Secret Service items in auth-source
* lisp/auth-source.el (auth-source-secrets-create): Use ´apply'.
(auth-source-secrets-saver): Handle `auth-source-save-behavior'
equal t.
* lisp/net/secrets.el (secrets-get-items): Do not call
`secrets-open-session' here ...
(top): ... but here.
* test/lisp/auth-source-tests.el
(auth-source-test-secrets-create-secret): Bind
`auth-source-save-behavior' to t. Cleanup.
* test/lisp/net/secrets-tests.el (secrets-test00-availability):
After loading secets.el, a session is already opened.
(secrets-test02-collections, secrets-test03-items)
(secrets-test04-search): Open a new session.