Ensure space for the null-terminator to solve heap corruption - #20428

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Also need change log and test. Make sure the test segfault without the patch but does not segfault with it.

Also see: https://docs.astropy.org/en/latest/index_dev.html

@Rob2688 please stop adding merge commits to this PR and instead work on resolving remaining asks. Thanks.

Hello sorry for the confusion. I'm still new to all this contribution stuff. I changed the log and I'm trying to test. I'll get back to you as soon as possible.

I've added the regression test to astropy/io/votable/tests/test_table.py as requested. All tests are passing and this PR is ready for final maintainer review.

@Rob2688 can you rebase to get rid of the merge commit?

For change log, instructions at https://github.com/astropy/astropy/blob/main/docs/changes/README.rst . Thanks!

@pllim Thank you for your review! I updated the test to use simple strings and added my changelog file