Undeterministic text extraction test

[Sinclert]

There is a non deterministic test within the tests/parsers/test_parser_text.py module.

In particular, the test_pdf_parsing test fails some of the times the full test-suite is run (using make test). When it fails, the error message looks as follows:

>   ???
E   AssertionError: assert 'UCLA/91/TEP/...954\n17\n\x0c' == 'UCLA/91/TEP/...954\n17\n\x0c'
E     Skipping 24340 identical leading characters in diff, use -v to show
E     Skipping 4581 identical trailing characters in diff, use -v to show
E       r′
E       r′ j ≤
E     + ≤
E       −
E     - ≤...
E     
E     ...Full output truncated (4 lines hidden), use '-vv' to show