Submit sitemap automatically

[rootwork]

Followup to #5, we should have an action that submits the sitemap every time that file changes.

Started building one, but so far it's skipping every time.

[rootwork]

It looks like the old action that is being used might be pinging the wrong address.

The correct address for submitting to Google is:

https://www.google.com/ping?sitemap=https://www.titaniumringsforever.com/sitemap.xml

[rootwork]

And Bing is:
https://www.bing.com/webmaster/ping.aspx?siteMap=https://www.titaniumringsforever.com/sitemap.xml

[rootwork]

This might be working? Need to check on another day to see if this workflow:

https://github.com/exotica-jewelry/ringsforever/actions?query=workflow%3A%22Sitemap+submitter%22

is actually generating an updated sitemap here:

https://search.google.com/u/2/search-console/sitemaps?resource_id=http%3A%2F%2Fwww.titaniumringsforever.com%2F&hl=en

[rootwork]

Folded it into one action:
5f01ee7#diff-87ee5504a3e25ac558b343724c905f2f7949e8cec3d92b9c4300bb922afa164f

Still need to check, then, if THIS action is submitting (it seems like it is):
https://github.com/exotica-jewelry/ringsforever/actions?query=workflow%3A%22Sitemap+generator%22

Ideally it should be changed so it only commits & submits (ha) when there is a change to the sitemap, not on every push to GH.

[rootwork]

It is definitely submitting; need to check if it only builds & submits when there's a change to the sitemap.