ensure context __exit__ is called during shell completion

[akhil-vempali]

The necessary modifications will ensure that the context's __exit__ function is called during shell completion, addressing the issue of unclosed file options.

fixes #2644

[AndreasBackx]

@akhil-vempali if you have some time available, we could hopefully get this into 8.2.0. If you do, could you make sure to:

1. Fix the now broken tests.
2. Add a test to prevent this from regressing.

[AndreasBackx]

@akhil-vempali thank you for your work. I continued in #2800 and merged it. I added you as a co-author as you already did great work identifying where the issue was and almost fixed it as well. There was a confusion of context objects that I rectified and I added a test case so we can prevent a regression.