Move experimental module querypoll to erc-notify

Move experimental module querypoll to erc-notify

* etc/ERC-NEWS: Announce migration of misplaced `querypoll' module from
erc-goodies.el to erc-notify.el.
* lisp/erc/erc-goodies.el: Move all definitions associated with
experimental module `querypoll' to erc-notify.
* lisp/erc/erc-notify.el (erc--querypoll-ring)
(erc--querypoll-timer, erc-querypoll-exclude-regexp)
(erc-querypoll-mode, erc-querypoll-enable, erc-querypoll-disable)
(erc--queries-current-p, erc-querypoll-period-params)
(erc--querypoll-compute-period, erc--querypoll-target-in-chan-p)
(erc--querypoll-get-length, erc--querypoll-get-next)
(erc--querypoll-subscribe, erc--querypoll-on-352)
(erc--querypoll-send): Move here from erc-goodies.
* test/lisp/erc/erc-goodies-tests.el (erc--querypoll-compute-period)
(erc--querypoll-target-in-chan-p, erc--querypoll-get-length)
(erc--querypoll-get-next): Move to new file erc-notify-tests.el.
* test/lisp/erc/erc-notify-tests.el: New file.  The `querypoll' module
was first introduced as part of bug#70928 in ERC 5.6.

(cherry picked from commit be3318baddbcb3ff607c784a14c1f21a70e392de)