Add ephemery config url and remove hardcoded config file

[gconnect]

PR Description

Fixed Issue(s)

fixes #9121

Documentation

• I thought about documentation and added the doc-change-required label to this PR if updates are required.

Changelog

• I thought about adding a changelog entry, and added one if I deemed necessary.

[gconnect]

@rolfyone please review when you have the time.

[tbenr]

@gconnect
Maybe to avoid using deprecated method you could use
URI.create("https://ephemery.dev/latest/metadata/config.yaml").toURL()

[rolfyone]

Thanks for raising the PR, I'll take a look.
I think potentially this change is more involved, but I'll dig into it.

[rolfyone]

I think the latest url has all the numbers right so really, we'd want to clean up a lot of what's currently done in 'ephemery' for updating config, we shouldn't need it any more.
I'm not sure that the location of this PR code is ideal, thats very low level, but it might be the right place - it just seems like because we don't need all the config update logic (from recollection)
Other minor observations like variables need to be final, and not using deprecated functions but I think the bigger problem is probably that we need to do more analysis.
We could potentially un-assign this and get someone else to do it if that sounds like a lot, but I don't really think this PR is what we are looking for.