test/eieio: Silence warnings about slots and obsolete name arg

test/eieio: Silence warnings about slots and obsolete name arg

* test/lisp/emacs-lisp/eieio-tests/eieio-test-methodinvoke.el
(eieio-test-method-order-list-3, eieio-test-method-order-list-6)
(eieio-test-method-order-list-7, eieio-test-method-order-list-8):
Delete obsolete name argument to constructors.
(eieio-test-method-order-list-4): Make sure backward compatibility is
active when testing the obsolete name arg.

* test/lisp/jsonrpc-tests.el (jsonrpc--call-with-emacsrpc-fixture):
Delete obsolete name argument to constructor.

* test/lisp/emacs-lisp/eieio-tests/eieio-tests.el (derived-value):
Silence unknown slot warning.

(cherry picked from commit 31c5fd3bfba31687de31e1e4c3d3501401f023bc)