Make parse_server_name more consistent

[Abdullah0sama]

Fixes #12122

Pull Request Checklist

• Pull request is based on the develop branch
• Pull request includes a changelog file. The entry should:
  • Be a short description of your change which makes sense to users. "Fixed a bug that prevented receiving messages from other servers." instead of "Moved X method from EventStore to EventWorkerStore.".
  • Use markdown where necessary, mostly for code blocks.
  • End with either a period (.) or an exclamation mark (!).
  • Start with a capital letter.
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• Code style is correct
  (run the linters)

Signed-off-by: Abdullah Osama abdullahosama15@gmail.com

[erikjohnston]

Thanks! In the test_validate_bad_server_names unit test can you add a check for ":80" please?

[erikjohnston]

Thanks!

[anoadragon453]

I've merged latest develop into this PR's branch in order to make CI pass. Unit tests were failing with the following backtrace:

error log

Error: 
Traceback (most recent call last):
  File "/tmp/tmp.A21RKCLSkU/tests/unittest.py", line 119, in new
    return code(orig, *args, **kwargs)
  File "/tmp/tmp.A21RKCLSkU/tests/unittest.py", line 163, in setUp
    return orig()
  File "/tmp/tmp.A21RKCLSkU/tests/unittest.py", line 271, in setUp
    self.hs = self.make_homeserver(self.reactor, self.clock)
  File "/tmp/tmp.A21RKCLSkU/tests/rest/media/v1/test_url_preview.py", line 95, in make_homeserver
    hs = self.setup_test_homeserver(config=config)
  File "/tmp/tmp.A21RKCLSkU/tests/unittest.py", line 516, in setup_test_homeserver
    config_obj.parse_config_dict(config, "", "")
  File "/synapse/build/debian/matrix-synapse-py3/opt/venvs/matrix-synapse/lib/python3.10/site-packages/synapse/config/_base.py", line 794, in parse_config_dict
    self.invoke_all(
  File "/synapse/build/debian/matrix-synapse-py3/opt/venvs/matrix-synapse/lib/python3.10/site-packages/synapse/config/_base.py", line 393, in invoke_all
    res[config_class.section] = getattr(config, func_name)(*args, **kwargs)
  File "/synapse/build/debian/matrix-synapse-py3/opt/venvs/matrix-synapse/lib/python3.10/site-packages/synapse/config/repository.py", line 208, in read_config
    check_requirements("url_preview")
  File "/synapse/build/debian/matrix-synapse-py3/opt/venvs/matrix-synapse/lib/python3.10/site-packages/synapse/util/check_dependencies.py", line 181, in check_requirements
    raise ValueError(f"Synapse {VERSION} does not provide the feature '{extra}'")
builtins.ValueError: Synapse 1.69.0rc1 does not provide the feature 'url_preview'

[DMRobertson]

I've merged latest develop into this PR's branch in order to make CI pass. Unit tests were failing with the following backtrace:
error log

Xref #14079