feature(html partition): parse pre tag (#642)
* feature(html partition): parse pre tag
* chore: update CHANGELOG.md
* style: black format xml.py
* Added tests dor html with pre tag
* remove skip test, update parse pre tag
* fix style
* chore: spell check
* chore: update changelog & version
* chore: update ingest test fixtures
* chore: add exception handling if `element.text` is `None` in `_read_xml`
* test: add more sanity testing on the `.text` content of the element(s)
* refactor: move the conditional logic for <pre> outside of the `try/except` block
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Co-authored-by: cragwolfe <crag@unstructured.io>
Co-authored-by: christinestraub <christinemstraub@gmail.com>
