fix(docx): isolate list state in table cells (#3294)

* fix(docx): isolate list state in table cells

Lists with the same numId in different table cells were incorrectly
merged. Added context manager to isolate list state during cell
processing. Includes test cases and updated ground truth files.

Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>

* style(docx): modernize type hints to use PEP 604 union syntax

Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>

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Signed-off-by: Cesar Berrospi Ramis <ceb@zurich.ibm.com>