Fix some naming issues involving query buffers in ERC

Fix some naming issues involving query buffers in ERC

* lisp/erc/erc-networks.el
(erc-networks-rename-surviving-target-buffer): Don't kill a surviving
target buffer when another, non-target buffer, possibly not even
belonging to ERC, already exists and sports the target's name.
(erc-networks--reconcile-buffer-names): Always append a network-ID
suffix to a target buffer's name if another buffer of that name
already exists.  (Bug#59976.)
* lisp/erc/erc.el (erc, erc-tls): Revise `:id' portion of doc strings.
Thanks to Mike Kazantsev for the suggestion and for filing this bug
and helping solve it.
* test/lisp/erc/erc-networks-tests.el:
(erc-networks-rename-surviving-target-buffer--query-non-target): Add
new test.
* test/lisp/erc/erc-scenarios-base-association-query.el: New file.
* test/lisp/erc/resources/base/assoc/queries/netnick.eld: New file.
* test/lisp/erc/resources/base/assoc/queries/non-erc.eld: New file.