[pyupgrade] Make example error out-of-the-box (UP023)

[MeGaGiGaGon]

Summary

Part of #18972

This PR makes deprecated-c-element-tree (UP023)'s example error out-of-the-box. I have no clue why the import xml.etree.cElementTree and from xml.etree import cElementTree cases are specifically carved out if they do not have an as ..., but the tests explicitly call this out, and that's how it is in pyupgrade's source as well.

ruff/crates/ruff_linter/resources/test/fixtures/pyupgrade/UP023.py

Lines 23 to 31 in b5c5f71

	# This should fix the second, but not the first invocation.
	import xml.etree.cElementTree, xml.etree.cElementTree as ET
	# The below items should NOT be changed.
	import xml.etree.cElementTree
	from .xml.etree.cElementTree import XML
	from xml.etree import cElementTree

Old example

from xml.etree import cElementTree

New example

from xml.etree import cElementTree as ET

The "Use instead" section was also updated similarly.

Test Plan

N/A, no functionality/tests affected

[github-actions]

ruff-ecosystem results

Linter (stable)

✅ ecosystem check detected no linter changes.

Linter (preview)

✅ ecosystem check detected no linter changes.

[dylwil3]

Thanks!