Fix broken issue rendering when initial ID is null

What does this MR do and why?

Fix broken issue rendering when initial ID is null

We added toString in !133621 (merged) but id/iid can be null on initial render (sometimes?)

!136022 (merged) was merged to fix this in %16.6, and this follow up MR is created to backport the fix in %16.5

Changelog: fixed

Broken example: omnibus-gitlab#8291 (closed)

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• This MR is backporting a bug fix, documentation update, or spec fix, previously merged in the default branch.
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