Support for v:oval

[lemonov]

Current version of library does not recognize v:oval shapes and does not return any text that is inside. Would be nice if it would return paragraph similar results to v:rect (or any other shape).

Test file: shapes.docx

Example

import mammoth

with open('shapes.docx', 'rb') as file:
    result = mammoth.convert_to_html(file)
    print(result.value)

Expected output

<p>Rectangle shape</p><p>Oval shape</p>

Actual output

<p>Rectangle shape</p>

Tested on:

Python 3.12.0
Ubuntu 20.04.1
mammoth 1.8.0