fixes #25162; fixup 0f5732bc8c: withValue for immut tab wrong chk cond

[litlighilit]

fixes #25162
ref #24825

[tersec]

Tests?

[litlighilit]

See source of
contains/hasKey/containsOrIncl and another variant of withValue

all use index >= 0 to mean key existing

[litlighilit]

The failed cases are those whose index == 0,
which is not ubiquitous example.

If really needing corresponding test added to tests/, I may add what I mentioned on the origin issue #25162

[ringabout]

Tests are added for preventing of regression. Though in this case, it could hardly regress. But it can also ease and accelerate review if tests are there to ensure that this patch works

[Araq]

@narimiran please backport

[github-actions]

Thanks for your hard work on this PR!
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