test: add shell-completion case for hidden BoolWithInverseFlag

[dearchap]

What type of PR is this?

(REQUIRED)

• cleanup

What this PR does / why we need it:

(REQUIRED)

Follow-up from review of #2388.

PR #2388 changed printFlagSuggestions in help.go to skip flags via the VisibleFlag/IsVisible() interface instead of the previous flag.(*BoolFlag) assertion. The previous check only skipped hidden bool flags, and because the *BoolFlag assertion does not match the *BoolWithInverseFlag concrete type, hidden BoolWithInverseFlags were also leaked into shell completion suggestions.

That leak is now fixed by the interface-based check, but the regression test table in TestDefaultCompleteWithFlags only covered the BoolFlag (hidden-bool) and StringFlag (new in #2388) cases.

This PR adds a BoolWithInverseFlag case to the TestDefaultCompleteWithFlags table — a hidden --excellent BoolWithInverseFlag alongside a visible --excitement one — to lock in the fix for this type too.

Which issue(s) this PR fixes:

(REQUIRED)

Fixes #2405

Special notes for your reviewer:

Verified the new test catches the regression: with the old *BoolFlag-only assertion restored in help.go, the case fails with the hidden --excellent leaking into the suggestions (--excellent\n--excitement\n). With the current interface-based check it passes.

Testing

Ran the focused test batch:

go test -count=1 -run "TestDefaultCompleteWithFlags" -v .

All cases pass, including the new typical-flag-suggestion-hidden-bool-with-inverse. make lint and go vet ./... are clean.

Release Notes

(REQUIRED)

NONE