Note:

For people stumbling upon this: After releasing this PR in v13.4 we became aware that is was unintentioally breaking. See here for details.

When ready closes #2416

Already tested

• polling
• nginx reverse proxy webhooks with letsencrypt (not passing cert to TG) & with self-signed certificate (passing cert to TG)

To be done:

• test having the built-in Webserver handle the SSL stuff. IISC I can't test that on my lolcal setup, though …
• double check if docs are updated enough
• unit tests
• add dreprecation of clean to Deprecation: v15 #2347

This also

• deprecated the clean argument in favor of drop_pending_updates as a) that conforms with the TG nomenclature, b) that name is more speaking
• adds the ip_address parameter of set_webhook to start_webhook (tbh I don't really understand what it's good for, do we need some special casing for that?)

When ready:

• Update the wiki page on webhooks according to the changes

Checklist for PRs

• Added .. versionadded:: version, .. versionchanged:: version or .. deprecated:: version to the docstrings for user facing changes (I did that but leaving it as todo here so we double check the version number before merging)