**What happens?**:
```
======================================================================
ERROR: testLinks (tests.page_tests.TestPageObject)
Test the different types of links from a page.
----------------------------------------------------------------------
Traceback (most recent call last):
File "/home/runner/work/pywikibot/pywikibot/tests/page_tests.py", line 534, in testLinks
iw = list(mainpage.interwiki(expand=True))
File "/home/runner/work/pywikibot/pywikibot/pywikibot/page/__init__.py", line 1381, in interwiki
if link.site != self.site:
File "/home/runner/work/pywikibot/pywikibot/pywikibot/page/__init__.py", line 5449, in site
self.parse()
File "/home/runner/work/pywikibot/pywikibot/pywikibot/page/__init__.py", line 5352, in parse
newsite = self._site.interwiki(prefix)
File "/home/runner/work/pywikibot/pywikibot/pywikibot/site/_apisite.py", line 141, in interwiki
return self._interwikimap[prefix].site
File "/home/runner/work/pywikibot/pywikibot/pywikibot/site/_interwikimap.py", line 78, in __getitem__
raise self._iw_sites[prefix].site
File "/home/runner/work/pywikibot/pywikibot/pywikibot/site/_interwikimap.py", line 26, in site
url=self.url, fam=None if self.local else self.prefix)
File "/home/runner/work/pywikibot/pywikibot/pywikibot/__init__.py", line 1184, in Site
code, fam = _code_fam_from_url(url, fam)
File "/home/runner/work/pywikibot/pywikibot/pywikibot/__init__.py", line 1097, in _code_fam_from_url
code = family.from_url(url)
File "/home/runner/work/pywikibot/pywikibot/pywikibot/family.py", line 858, in from_url
'not supported (T111513).'.format(url, suffix))
ValueError: Url: https://lists.wikimedia.org/postorius/lists/$1.lists.wikimedia.org/
Text .lists.wikimedia.org/ after the $1 placeholder is not supported (T111513).
```
https://github.com/wikimedia/pywikibot/runs/4585427682?check_suite_focus=true
**Software version (if not a Wikimedia wiki), browser information, screenshots, other information, etc**:
Pywikibot 7.0.0.dev0