TST/CLN: Fix/clean pytables test
While working on #23731, I sometimes got a failing test for pytables -- based on the rest of the test, it seemed pretty clear that the `_maybe_remove(store, 'xx')` was not consistently used throughout the test, and so I thought I'd add it. I'm guessing the CI never hits this failure because it seems it would need more replications for that.
Hello @h-vetinari! Thanks for submitting the PR.

 - There are no PEP8 issues in the file [`pandas/tests/io/test_pytables.py`](https://github.com/h-vetinari/pandas/blob/c9dfec42e54240d40d122133189d81cb78c3ed4c/pandas/tests/io/test_pytables.py) !

 Failure is due to #23726 not sure this actually solves a problem. As I laid out in the OP, this solves a flaky test that doesn't fail in the CI (clean image every time), but it failed about 10x for me locally, and it was obvious from the error that the same input hat been written to a store key twice. Hence adding the  `_maybe_remove` consistently.

It's a small change, but why not make the test suite more stable? ok I don't think these actually fix anything, but can't hur

that original function should be a contextmanager anyhow (welcome PR on that).