fix(complete): restore nospace in bash when reply ends in =/:

[mernen]

This is a fix for #5980.

Tested with the same POC app, app-name --path sr<TAB> now completes to src/ with no trailing space, and <TAB> again completes to src/main.rs (with trailing space), as expected.

Also tested with jj.

[epage]

Tested with the same POC app, app-name --path sr now completes to src/ with no trailing space, and again completes to src/main.rs (with trailing space), as expected.

We have end-to-end tests for bash completions. Would you be able to reproduce this in that scenario so we can have a test for this?

Preferrably, we split the PR up into two commits

1. Add the test, showing the current broken behavior
2. Fix the behavior and update the test

[mernen]

Apologies, I hadn't noticed the project already has testing infrastructure for simulating a terminal! I've now included a proper test. Also, I see this is very similar to an existing test for issue #5239, except this one is for dynamic completion.

[epage]

Thanks!